Chapter
stringclasses
18 values
sentence_range
stringlengths
3
9
Text
stringlengths
7
7.34k
9
1139-1142
Let CE represent a tangent plane drawn from the point C on to the sphere Then, AE = v2 t and CE would represent the refracted wavefront If we now consider the triangles ABC and AEC, we readily obtain sin i = 1 BC AC AC =v τ (10 1) and sin r = 2 AE AC AC =v τ (10
9
1140-1143
Then, AE = v2 t and CE would represent the refracted wavefront If we now consider the triangles ABC and AEC, we readily obtain sin i = 1 BC AC AC =v τ (10 1) and sin r = 2 AE AC AC =v τ (10 2) where i and r are the angles of incidence and refraction, respectively
9
1141-1144
If we now consider the triangles ABC and AEC, we readily obtain sin i = 1 BC AC AC =v τ (10 1) and sin r = 2 AE AC AC =v τ (10 2) where i and r are the angles of incidence and refraction, respectively Thus we obtain 1 2 sin sin i v r =v (10
9
1142-1145
1) and sin r = 2 AE AC AC =v τ (10 2) where i and r are the angles of incidence and refraction, respectively Thus we obtain 1 2 sin sin i v r =v (10 3) From the above equation, we get the important result that if r < i (i
9
1143-1146
2) where i and r are the angles of incidence and refraction, respectively Thus we obtain 1 2 sin sin i v r =v (10 3) From the above equation, we get the important result that if r < i (i e
9
1144-1147
Thus we obtain 1 2 sin sin i v r =v (10 3) From the above equation, we get the important result that if r < i (i e , if the ray bends toward the normal), the speed of the light wave in the second medium (v2) will be less then the speed of the light wave in the first medium (v1)
9
1145-1148
3) From the above equation, we get the important result that if r < i (i e , if the ray bends toward the normal), the speed of the light wave in the second medium (v2) will be less then the speed of the light wave in the first medium (v1) This prediction is opposite to the prediction from the corpuscular model of light and as later experiments showed, the prediction of the wave theory is correct
9
1146-1149
e , if the ray bends toward the normal), the speed of the light wave in the second medium (v2) will be less then the speed of the light wave in the first medium (v1) This prediction is opposite to the prediction from the corpuscular model of light and as later experiments showed, the prediction of the wave theory is correct Now, if c represents the speed of light in vacuum, then, 1 1 c n =v (10
9
1147-1150
, if the ray bends toward the normal), the speed of the light wave in the second medium (v2) will be less then the speed of the light wave in the first medium (v1) This prediction is opposite to the prediction from the corpuscular model of light and as later experiments showed, the prediction of the wave theory is correct Now, if c represents the speed of light in vacuum, then, 1 1 c n =v (10 4) and n2 = 2 vc (10
9
1148-1151
This prediction is opposite to the prediction from the corpuscular model of light and as later experiments showed, the prediction of the wave theory is correct Now, if c represents the speed of light in vacuum, then, 1 1 c n =v (10 4) and n2 = 2 vc (10 5) are known as the refractive indices of medium 1 and medium 2, respectively
9
1149-1152
Now, if c represents the speed of light in vacuum, then, 1 1 c n =v (10 4) and n2 = 2 vc (10 5) are known as the refractive indices of medium 1 and medium 2, respectively In terms of the refractive indices, Eq
9
1150-1153
4) and n2 = 2 vc (10 5) are known as the refractive indices of medium 1 and medium 2, respectively In terms of the refractive indices, Eq (10
9
1151-1154
5) are known as the refractive indices of medium 1 and medium 2, respectively In terms of the refractive indices, Eq (10 3) can be written as n1 sin i = n2 sin r (10
9
1152-1155
In terms of the refractive indices, Eq (10 3) can be written as n1 sin i = n2 sin r (10 6) This is the Snell’s law of refraction
9
1153-1156
(10 3) can be written as n1 sin i = n2 sin r (10 6) This is the Snell’s law of refraction Further, if l1 and l 2 denote the wavelengths of light in medium 1 and medium 2, respectively and if the distance BC is equal to l 1 then the distance AE will be equal to l 2 (because if the crest from B has reached C in time t, then the crest from A should have also reached E in time t ); thus, 1 1 2 2 BC AE v v λλ = = or 1 2 1 2 v v λ =λ (10
9
1154-1157
3) can be written as n1 sin i = n2 sin r (10 6) This is the Snell’s law of refraction Further, if l1 and l 2 denote the wavelengths of light in medium 1 and medium 2, respectively and if the distance BC is equal to l 1 then the distance AE will be equal to l 2 (because if the crest from B has reached C in time t, then the crest from A should have also reached E in time t ); thus, 1 1 2 2 BC AE v v λλ = = or 1 2 1 2 v v λ =λ (10 7) CHRISTIAAN HUYGENS (1629 – 1695) Christiaan Huygens (1629 – 1695) Dutch physicist, astronomer, mathematician and the founder of the wave theory of light
9
1155-1158
6) This is the Snell’s law of refraction Further, if l1 and l 2 denote the wavelengths of light in medium 1 and medium 2, respectively and if the distance BC is equal to l 1 then the distance AE will be equal to l 2 (because if the crest from B has reached C in time t, then the crest from A should have also reached E in time t ); thus, 1 1 2 2 BC AE v v λλ = = or 1 2 1 2 v v λ =λ (10 7) CHRISTIAAN HUYGENS (1629 – 1695) Christiaan Huygens (1629 – 1695) Dutch physicist, astronomer, mathematician and the founder of the wave theory of light His book, Treatise on light, makes fascinating reading even today
9
1156-1159
Further, if l1 and l 2 denote the wavelengths of light in medium 1 and medium 2, respectively and if the distance BC is equal to l 1 then the distance AE will be equal to l 2 (because if the crest from B has reached C in time t, then the crest from A should have also reached E in time t ); thus, 1 1 2 2 BC AE v v λλ = = or 1 2 1 2 v v λ =λ (10 7) CHRISTIAAN HUYGENS (1629 – 1695) Christiaan Huygens (1629 – 1695) Dutch physicist, astronomer, mathematician and the founder of the wave theory of light His book, Treatise on light, makes fascinating reading even today He brilliantly explained the double refraction shown by the mineral calcite in this work in addition to reflection and refraction
9
1157-1160
7) CHRISTIAAN HUYGENS (1629 – 1695) Christiaan Huygens (1629 – 1695) Dutch physicist, astronomer, mathematician and the founder of the wave theory of light His book, Treatise on light, makes fascinating reading even today He brilliantly explained the double refraction shown by the mineral calcite in this work in addition to reflection and refraction He was the first to analyse circular and simple harmonic motion and designed and built improved clocks and telescopes
9
1158-1161
His book, Treatise on light, makes fascinating reading even today He brilliantly explained the double refraction shown by the mineral calcite in this work in addition to reflection and refraction He was the first to analyse circular and simple harmonic motion and designed and built improved clocks and telescopes He discovered the true geometry of Saturn’s rings
9
1159-1162
He brilliantly explained the double refraction shown by the mineral calcite in this work in addition to reflection and refraction He was the first to analyse circular and simple harmonic motion and designed and built improved clocks and telescopes He discovered the true geometry of Saturn’s rings Rationalised 2023-24 Physics 260 The above equation implies that when a wave gets refracted into a denser medium (v1 > v2) the wavelength and the speed of propagation decrease but the frequency n (= v/l) remains the same
9
1160-1163
He was the first to analyse circular and simple harmonic motion and designed and built improved clocks and telescopes He discovered the true geometry of Saturn’s rings Rationalised 2023-24 Physics 260 The above equation implies that when a wave gets refracted into a denser medium (v1 > v2) the wavelength and the speed of propagation decrease but the frequency n (= v/l) remains the same 10
9
1161-1164
He discovered the true geometry of Saturn’s rings Rationalised 2023-24 Physics 260 The above equation implies that when a wave gets refracted into a denser medium (v1 > v2) the wavelength and the speed of propagation decrease but the frequency n (= v/l) remains the same 10 3
9
1162-1165
Rationalised 2023-24 Physics 260 The above equation implies that when a wave gets refracted into a denser medium (v1 > v2) the wavelength and the speed of propagation decrease but the frequency n (= v/l) remains the same 10 3 2 Refraction at a rarer medium We now consider refraction of a plane wave at a rarer medium, i
9
1163-1166
10 3 2 Refraction at a rarer medium We now consider refraction of a plane wave at a rarer medium, i e
9
1164-1167
3 2 Refraction at a rarer medium We now consider refraction of a plane wave at a rarer medium, i e , v2 > v1
9
1165-1168
2 Refraction at a rarer medium We now consider refraction of a plane wave at a rarer medium, i e , v2 > v1 Proceeding in an exactly similar manner we can construct a refracted wavefront as shown in Fig
9
1166-1169
e , v2 > v1 Proceeding in an exactly similar manner we can construct a refracted wavefront as shown in Fig 10
9
1167-1170
, v2 > v1 Proceeding in an exactly similar manner we can construct a refracted wavefront as shown in Fig 10 5
9
1168-1171
Proceeding in an exactly similar manner we can construct a refracted wavefront as shown in Fig 10 5 The angle of refraction will now be greater than angle of incidence; however, we will still have n1 sin i = n2 sin r
9
1169-1172
10 5 The angle of refraction will now be greater than angle of incidence; however, we will still have n1 sin i = n2 sin r We define an angle ic by the following equation 2 1 sin c n i =n (10
9
1170-1173
5 The angle of refraction will now be greater than angle of incidence; however, we will still have n1 sin i = n2 sin r We define an angle ic by the following equation 2 1 sin c n i =n (10 8) Thus, if i = ic then sin r = 1 and r = 90°
9
1171-1174
The angle of refraction will now be greater than angle of incidence; however, we will still have n1 sin i = n2 sin r We define an angle ic by the following equation 2 1 sin c n i =n (10 8) Thus, if i = ic then sin r = 1 and r = 90° Obviously, for i > ic, there can not be any refracted wave
9
1172-1175
We define an angle ic by the following equation 2 1 sin c n i =n (10 8) Thus, if i = ic then sin r = 1 and r = 90° Obviously, for i > ic, there can not be any refracted wave The angle ic is known as the critical angle and for all angles of incidence greater than the critical angle, we will not have any refracted wave and the wave will undergo what is known as total internal reflection
9
1173-1176
8) Thus, if i = ic then sin r = 1 and r = 90° Obviously, for i > ic, there can not be any refracted wave The angle ic is known as the critical angle and for all angles of incidence greater than the critical angle, we will not have any refracted wave and the wave will undergo what is known as total internal reflection The phenomenon of total internal reflection and its applications was discussed in Section 9
9
1174-1177
Obviously, for i > ic, there can not be any refracted wave The angle ic is known as the critical angle and for all angles of incidence greater than the critical angle, we will not have any refracted wave and the wave will undergo what is known as total internal reflection The phenomenon of total internal reflection and its applications was discussed in Section 9 4
9
1175-1178
The angle ic is known as the critical angle and for all angles of incidence greater than the critical angle, we will not have any refracted wave and the wave will undergo what is known as total internal reflection The phenomenon of total internal reflection and its applications was discussed in Section 9 4 Demonstration of interference, diffraction, refraction, resonance and Doppler effect http://www
9
1176-1179
The phenomenon of total internal reflection and its applications was discussed in Section 9 4 Demonstration of interference, diffraction, refraction, resonance and Doppler effect http://www falstad
9
1177-1180
4 Demonstration of interference, diffraction, refraction, resonance and Doppler effect http://www falstad com/ripple/ FIGURE 10
9
1178-1181
Demonstration of interference, diffraction, refraction, resonance and Doppler effect http://www falstad com/ripple/ FIGURE 10 5 Refraction of a plane wave incident on a rarer medium for which v2 > v1
9
1179-1182
falstad com/ripple/ FIGURE 10 5 Refraction of a plane wave incident on a rarer medium for which v2 > v1 The plane wave bends away from the normal
9
1180-1183
com/ripple/ FIGURE 10 5 Refraction of a plane wave incident on a rarer medium for which v2 > v1 The plane wave bends away from the normal 10
9
1181-1184
5 Refraction of a plane wave incident on a rarer medium for which v2 > v1 The plane wave bends away from the normal 10 3
9
1182-1185
The plane wave bends away from the normal 10 3 3 Reflection of a plane wave by a plane surface We next consider a plane wave AB incident at an angle i on a reflecting surface MN
9
1183-1186
10 3 3 Reflection of a plane wave by a plane surface We next consider a plane wave AB incident at an angle i on a reflecting surface MN If v represents the speed of the wave in the medium and if t represents the time taken by the wavefront to advance from the point B to C then the distance BC = vt In order to construct the reflected wavefront we draw a sphere of radius vt from the point A as shown in Fig
9
1184-1187
3 3 Reflection of a plane wave by a plane surface We next consider a plane wave AB incident at an angle i on a reflecting surface MN If v represents the speed of the wave in the medium and if t represents the time taken by the wavefront to advance from the point B to C then the distance BC = vt In order to construct the reflected wavefront we draw a sphere of radius vt from the point A as shown in Fig 10
9
1185-1188
3 Reflection of a plane wave by a plane surface We next consider a plane wave AB incident at an angle i on a reflecting surface MN If v represents the speed of the wave in the medium and if t represents the time taken by the wavefront to advance from the point B to C then the distance BC = vt In order to construct the reflected wavefront we draw a sphere of radius vt from the point A as shown in Fig 10 6
9
1186-1189
If v represents the speed of the wave in the medium and if t represents the time taken by the wavefront to advance from the point B to C then the distance BC = vt In order to construct the reflected wavefront we draw a sphere of radius vt from the point A as shown in Fig 10 6 Let CE represent the tangent plane drawn from the point C to this sphere
9
1187-1190
10 6 Let CE represent the tangent plane drawn from the point C to this sphere Obviously AE = BC = vt Rationalised 2023-24 261 Wave Optics FIGURE 10
9
1188-1191
6 Let CE represent the tangent plane drawn from the point C to this sphere Obviously AE = BC = vt Rationalised 2023-24 261 Wave Optics FIGURE 10 6 Reflection of a plane wave AB by the reflecting surface MN
9
1189-1192
Let CE represent the tangent plane drawn from the point C to this sphere Obviously AE = BC = vt Rationalised 2023-24 261 Wave Optics FIGURE 10 6 Reflection of a plane wave AB by the reflecting surface MN AB and CE represent incident and reflected wavefronts
9
1190-1193
Obviously AE = BC = vt Rationalised 2023-24 261 Wave Optics FIGURE 10 6 Reflection of a plane wave AB by the reflecting surface MN AB and CE represent incident and reflected wavefronts FIGURE 10
9
1191-1194
6 Reflection of a plane wave AB by the reflecting surface MN AB and CE represent incident and reflected wavefronts FIGURE 10 7 Refraction of a plane wave by (a) a thin prism, (b) a convex lens
9
1192-1195
AB and CE represent incident and reflected wavefronts FIGURE 10 7 Refraction of a plane wave by (a) a thin prism, (b) a convex lens (c) Reflection of a plane wave by a concave mirror
9
1193-1196
FIGURE 10 7 Refraction of a plane wave by (a) a thin prism, (b) a convex lens (c) Reflection of a plane wave by a concave mirror If we now consider the triangles EAC and BAC we will find that they are congruent and therefore, the angles i and r (as shown in Fig
9
1194-1197
7 Refraction of a plane wave by (a) a thin prism, (b) a convex lens (c) Reflection of a plane wave by a concave mirror If we now consider the triangles EAC and BAC we will find that they are congruent and therefore, the angles i and r (as shown in Fig 10
9
1195-1198
(c) Reflection of a plane wave by a concave mirror If we now consider the triangles EAC and BAC we will find that they are congruent and therefore, the angles i and r (as shown in Fig 10 6) would be equal
9
1196-1199
If we now consider the triangles EAC and BAC we will find that they are congruent and therefore, the angles i and r (as shown in Fig 10 6) would be equal This is the law of reflection
9
1197-1200
10 6) would be equal This is the law of reflection Once we have the laws of reflection and refraction, the behaviour of prisms, lenses, and mirrors can be understood
9
1198-1201
6) would be equal This is the law of reflection Once we have the laws of reflection and refraction, the behaviour of prisms, lenses, and mirrors can be understood These phenomena were discussed in detail in Chapter 9 on the basis of rectilinear propagation of light
9
1199-1202
This is the law of reflection Once we have the laws of reflection and refraction, the behaviour of prisms, lenses, and mirrors can be understood These phenomena were discussed in detail in Chapter 9 on the basis of rectilinear propagation of light Here we just describe the behaviour of the wavefronts as they undergo reflection or refraction
9
1200-1203
Once we have the laws of reflection and refraction, the behaviour of prisms, lenses, and mirrors can be understood These phenomena were discussed in detail in Chapter 9 on the basis of rectilinear propagation of light Here we just describe the behaviour of the wavefronts as they undergo reflection or refraction In Fig
9
1201-1204
These phenomena were discussed in detail in Chapter 9 on the basis of rectilinear propagation of light Here we just describe the behaviour of the wavefronts as they undergo reflection or refraction In Fig 10
9
1202-1205
Here we just describe the behaviour of the wavefronts as they undergo reflection or refraction In Fig 10 7(a) we consider a plane wave passing through a thin prism
9
1203-1206
In Fig 10 7(a) we consider a plane wave passing through a thin prism Clearly, since the speed of light waves is less in glass, the lower portion of the incoming wavefront (which travels through the greatest thickness of glass) will get delayed resulting in a tilt in the emerging wavefront as shown in the figure
9
1204-1207
10 7(a) we consider a plane wave passing through a thin prism Clearly, since the speed of light waves is less in glass, the lower portion of the incoming wavefront (which travels through the greatest thickness of glass) will get delayed resulting in a tilt in the emerging wavefront as shown in the figure In Fig
9
1205-1208
7(a) we consider a plane wave passing through a thin prism Clearly, since the speed of light waves is less in glass, the lower portion of the incoming wavefront (which travels through the greatest thickness of glass) will get delayed resulting in a tilt in the emerging wavefront as shown in the figure In Fig 10
9
1206-1209
Clearly, since the speed of light waves is less in glass, the lower portion of the incoming wavefront (which travels through the greatest thickness of glass) will get delayed resulting in a tilt in the emerging wavefront as shown in the figure In Fig 10 7(b) we consider a plane wave incident on a thin convex lens; the central part of the incident plane wave traverses the thickest portion of the lens and is delayed the most
9
1207-1210
In Fig 10 7(b) we consider a plane wave incident on a thin convex lens; the central part of the incident plane wave traverses the thickest portion of the lens and is delayed the most The emerging wavefront has a depression at the centre and therefore the wavefront becomes spherical and converges to the point F which is known as the focus
9
1208-1211
10 7(b) we consider a plane wave incident on a thin convex lens; the central part of the incident plane wave traverses the thickest portion of the lens and is delayed the most The emerging wavefront has a depression at the centre and therefore the wavefront becomes spherical and converges to the point F which is known as the focus In Fig
9
1209-1212
7(b) we consider a plane wave incident on a thin convex lens; the central part of the incident plane wave traverses the thickest portion of the lens and is delayed the most The emerging wavefront has a depression at the centre and therefore the wavefront becomes spherical and converges to the point F which is known as the focus In Fig 10
9
1210-1213
The emerging wavefront has a depression at the centre and therefore the wavefront becomes spherical and converges to the point F which is known as the focus In Fig 10 7(c) a plane wave is incident on a concave mirror and on reflection we have a spherical wave converging to the focal point F
9
1211-1214
In Fig 10 7(c) a plane wave is incident on a concave mirror and on reflection we have a spherical wave converging to the focal point F In a similar manner, we can understand refraction and reflection by concave lenses and convex mirrors
9
1212-1215
10 7(c) a plane wave is incident on a concave mirror and on reflection we have a spherical wave converging to the focal point F In a similar manner, we can understand refraction and reflection by concave lenses and convex mirrors From the above discussion it follows that the total time taken from a point on the object to the corresponding point on the image is the same measured along any ray
9
1213-1216
7(c) a plane wave is incident on a concave mirror and on reflection we have a spherical wave converging to the focal point F In a similar manner, we can understand refraction and reflection by concave lenses and convex mirrors From the above discussion it follows that the total time taken from a point on the object to the corresponding point on the image is the same measured along any ray For example, when a convex lens focusses light to form a real image, although the ray going through the centre traverses a shorter path, but because of the slower speed in glass, the time taken is the same as for rays travelling near the edge of the lens
9
1214-1217
In a similar manner, we can understand refraction and reflection by concave lenses and convex mirrors From the above discussion it follows that the total time taken from a point on the object to the corresponding point on the image is the same measured along any ray For example, when a convex lens focusses light to form a real image, although the ray going through the centre traverses a shorter path, but because of the slower speed in glass, the time taken is the same as for rays travelling near the edge of the lens Rationalised 2023-24 Physics 262 10
9
1215-1218
From the above discussion it follows that the total time taken from a point on the object to the corresponding point on the image is the same measured along any ray For example, when a convex lens focusses light to form a real image, although the ray going through the centre traverses a shorter path, but because of the slower speed in glass, the time taken is the same as for rays travelling near the edge of the lens Rationalised 2023-24 Physics 262 10 4 COHERENT AND INCOHERENT ADDITION OF WAVES In this section we will discuss the interference pattern produced by the superposition of two waves
9
1216-1219
For example, when a convex lens focusses light to form a real image, although the ray going through the centre traverses a shorter path, but because of the slower speed in glass, the time taken is the same as for rays travelling near the edge of the lens Rationalised 2023-24 Physics 262 10 4 COHERENT AND INCOHERENT ADDITION OF WAVES In this section we will discuss the interference pattern produced by the superposition of two waves You may recall that we had discussed the superposition principle in Chapter 14 of your Class XI textbook
9
1217-1220
Rationalised 2023-24 Physics 262 10 4 COHERENT AND INCOHERENT ADDITION OF WAVES In this section we will discuss the interference pattern produced by the superposition of two waves You may recall that we had discussed the superposition principle in Chapter 14 of your Class XI textbook Indeed the entire field of interference is based on the superposition principle according to which at a particular point in the medium, the resultant displacement produced by a number of waves is the vector sum of the displace- ments produced by each of the waves
9
1218-1221
4 COHERENT AND INCOHERENT ADDITION OF WAVES In this section we will discuss the interference pattern produced by the superposition of two waves You may recall that we had discussed the superposition principle in Chapter 14 of your Class XI textbook Indeed the entire field of interference is based on the superposition principle according to which at a particular point in the medium, the resultant displacement produced by a number of waves is the vector sum of the displace- ments produced by each of the waves Consider two needles S1 and S2 moving periodically up and down in an identical fashion in a trough of water [Fig
9
1219-1222
You may recall that we had discussed the superposition principle in Chapter 14 of your Class XI textbook Indeed the entire field of interference is based on the superposition principle according to which at a particular point in the medium, the resultant displacement produced by a number of waves is the vector sum of the displace- ments produced by each of the waves Consider two needles S1 and S2 moving periodically up and down in an identical fashion in a trough of water [Fig 10
9
1220-1223
Indeed the entire field of interference is based on the superposition principle according to which at a particular point in the medium, the resultant displacement produced by a number of waves is the vector sum of the displace- ments produced by each of the waves Consider two needles S1 and S2 moving periodically up and down in an identical fashion in a trough of water [Fig 10 8(a)]
9
1221-1224
Consider two needles S1 and S2 moving periodically up and down in an identical fashion in a trough of water [Fig 10 8(a)] They produce two water waves, and at a particular point, the phase difference between the displacements produced by each of the waves does not change with time; when this happens the two sources are said to be coherent
9
1222-1225
10 8(a)] They produce two water waves, and at a particular point, the phase difference between the displacements produced by each of the waves does not change with time; when this happens the two sources are said to be coherent Figure 10
9
1223-1226
8(a)] They produce two water waves, and at a particular point, the phase difference between the displacements produced by each of the waves does not change with time; when this happens the two sources are said to be coherent Figure 10 8(b) shows the position of crests (solid circles) and troughs (dashed circles) at a given instant of time
9
1224-1227
They produce two water waves, and at a particular point, the phase difference between the displacements produced by each of the waves does not change with time; when this happens the two sources are said to be coherent Figure 10 8(b) shows the position of crests (solid circles) and troughs (dashed circles) at a given instant of time Consider a point P for which S1 P = S2 P EXAMPLE 10
9
1225-1228
Figure 10 8(b) shows the position of crests (solid circles) and troughs (dashed circles) at a given instant of time Consider a point P for which S1 P = S2 P EXAMPLE 10 1 Example 10
9
1226-1229
8(b) shows the position of crests (solid circles) and troughs (dashed circles) at a given instant of time Consider a point P for which S1 P = S2 P EXAMPLE 10 1 Example 10 1 (a) When monochromatic light is incident on a surface separating two media, the reflected and refracted light both have the same frequency as the incident frequency
9
1227-1230
Consider a point P for which S1 P = S2 P EXAMPLE 10 1 Example 10 1 (a) When monochromatic light is incident on a surface separating two media, the reflected and refracted light both have the same frequency as the incident frequency Explain why
9
1228-1231
1 Example 10 1 (a) When monochromatic light is incident on a surface separating two media, the reflected and refracted light both have the same frequency as the incident frequency Explain why (b) When light travels from a rarer to a denser medium, the speed decreases
9
1229-1232
1 (a) When monochromatic light is incident on a surface separating two media, the reflected and refracted light both have the same frequency as the incident frequency Explain why (b) When light travels from a rarer to a denser medium, the speed decreases Does the reduction in speed imply a reduction in the energy carried by the light wave
9
1230-1233
Explain why (b) When light travels from a rarer to a denser medium, the speed decreases Does the reduction in speed imply a reduction in the energy carried by the light wave (c) In the wave picture of light, intensity of light is determined by the square of the amplitude of the wave
9
1231-1234
(b) When light travels from a rarer to a denser medium, the speed decreases Does the reduction in speed imply a reduction in the energy carried by the light wave (c) In the wave picture of light, intensity of light is determined by the square of the amplitude of the wave What determines the intensity of light in the photon picture of light
9
1232-1235
Does the reduction in speed imply a reduction in the energy carried by the light wave (c) In the wave picture of light, intensity of light is determined by the square of the amplitude of the wave What determines the intensity of light in the photon picture of light Solution (a) Reflection and refraction arise through interaction of incident light with the atomic constituents of matter
9
1233-1236
(c) In the wave picture of light, intensity of light is determined by the square of the amplitude of the wave What determines the intensity of light in the photon picture of light Solution (a) Reflection and refraction arise through interaction of incident light with the atomic constituents of matter Atoms may be viewed as oscillators, which take up the frequency of the external agency (light) causing forced oscillations
9
1234-1237
What determines the intensity of light in the photon picture of light Solution (a) Reflection and refraction arise through interaction of incident light with the atomic constituents of matter Atoms may be viewed as oscillators, which take up the frequency of the external agency (light) causing forced oscillations The frequency of light emitted by a charged oscillator equals its frequency of oscillation
9
1235-1238
Solution (a) Reflection and refraction arise through interaction of incident light with the atomic constituents of matter Atoms may be viewed as oscillators, which take up the frequency of the external agency (light) causing forced oscillations The frequency of light emitted by a charged oscillator equals its frequency of oscillation Thus, the frequency of scattered light equals the frequency of incident light
9
1236-1239
Atoms may be viewed as oscillators, which take up the frequency of the external agency (light) causing forced oscillations The frequency of light emitted by a charged oscillator equals its frequency of oscillation Thus, the frequency of scattered light equals the frequency of incident light (b) No
9
1237-1240
The frequency of light emitted by a charged oscillator equals its frequency of oscillation Thus, the frequency of scattered light equals the frequency of incident light (b) No Energy carried by a wave depends on the amplitude of the wave, not on the speed of wave propagation
9
1238-1241
Thus, the frequency of scattered light equals the frequency of incident light (b) No Energy carried by a wave depends on the amplitude of the wave, not on the speed of wave propagation (c) For a given frequency, intensity of light in the photon picture is determined by the number of photons crossing an unit area per unit time