DP024 FLIPBOOK 3 OF 3 (TOPIC 6-7)

THE GREEK ALPHABET

A  Alpha

B  Beta

  Gamma

  Delta

  Epsilon

  Zeta

  Eta

  Theta

  Iota

  Kappa

  Lambda

  Mu

  Nu.

  Xi

  Omicron

  Pi

  Rho

  Sigma

  Tau

  Upsilon

  ,  Phi

  Chi

  Psi

  Omega

i

LIST OF SELECTED CONSTANT VALUES
SENARAI NILAI PEMALAR TERPILIH

ii

LIST OF SELECTED CONSTANT VALUES
SENARAI NILAI PEMALAR TERPILIH

iii

LIST OF SELECTED FORMULAE
SENARAI RUMUS TERPILIH

1. a    2 x

2. x  A sin t B  o NI
17. 2R
v  dx
3. dt B  o NI
18.  L
a  dv 19.   B  A
4. dt 20. Φ = N
21. ε  Blvsin
5. y(x,t)  A sin(t  kx)

v  dy  NA dB
6. dt

7. v  f 22. ε dt

I  dQ  NB dA
8. dt dt
23. ε
  RA
9. l 24. r  2 f

10. Reff  R1  R2  R3  ... Rn 1 11
25. f u v
1  1  1  1  ... 1
11. Reff R1 R2 R3 Rn m  hi   v
26. ho u
1  1  1  1  ... 1
12. Ceff C1 C2 C3 Cn ym  mD
d
27.

13. Ceff  C1  C2  C3  ... Cn  m  1 D

t ym   2
d
14. Q  Qo e RC 28.

Q  Qo 1 - e t  y  D
RC 29. d

15.

B  oI
16. 2R

iv

TOPIC 6
GEOMETRICAL

OPTICS

6.1 Reflection at a spherical surface
a) State radius of curvature, =2 for spherical mirror.

b) Sketch ray diagrams with a minimum of two rays to state the
characteristicsof image formed by spherical mirrors.

c) Use mirror equation, 1/ =1/ +1/ for real object only.
*Sign convention for focal length, f:
i) Positive f for concave mirror.
ii) Negative f for convex mirror.

d) Define magnification equation.
e) Use magnification =ℎ /ℎ =− / respectively.
6.2 Thin lenses

a) Sketch ray diagrams with a minimum of two rays to
determine thecharacteristics of image formed by concave
and convex lenses.

b) Use thin lens equation, 1/ =1/ +1/ for real object only.
*Sign convention for focal length, f:
iii) Positive f for convex lens.
iv) Negative f for concave lens.

c) Define magnification.
d) Use magnification =ℎ /ℎ =− / respectively.

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OBJECTIVE QUESTIONS

(C1 & C2, PLO 1, MQF LOD 1)

1. Which best describes the image of a concave mirror when an object is located at
a point between the focal point and the center of curvature of mirror?
A. real, inverted and magnification less than one.
B. virtual, upright and magnification less than one.
C. real, inverted and magnification greater than one.
D. virtual, upright and magnification greater than one.

2. An object is placed at the focal point in front of a concave mirror. The image is located
at
A. infinity.
B. the focal point.
C. the centre of curvature.
D. the between focal length and centre of curvature.

3. An object is placed in front of a convex mirror. The image produced is
A. real, upright and magnified.
B. real, upright and diminished.
C. virtual, upright and magnified.
D. virtual, upright and diminished.

4. When an object is located at twice of its focal length for a convex lens, the image
formed is
A. upright
B. inverted
C. diminished
D. same size as the object

5. The characteristics of image formed by concave lens are
A. real, upright and magnified.
B. real, upright and diminished.
C. virtual, upright and magnified.
D. virtual, upright and diminished.

Answer:
1. C 2. B 3. D 4. D 5. D

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STRUCTURED QUESTIONS

(C3, PLO 4, CTPS 2, MQF LOD 6)

1. A 1.8 m tall shopper in a department store is 5.8 m from a convex security mirror.
The shopper notices that his image in the mirror appears to be only16.3 cm tall.
(a) Calculate the magnification.
(b) Calculate the image distance.
(c) Calculate the focal length.
(d) Calculate the radius of curvature.
(e) Sketch a ray diagram to show the formation of the image.

2. A vertical object is placed in front of a spherical mirror and the linear magnification of
the image is 3. If an upright image is formed 30 cm from the pole of the mirror,
(a) state the type of spherical mirror.
(b) sketch a ray diagram to show the formation of the image.
(c) calculate the distance of the object from the pole of the mirror.
(d) calculate the focal length of the mirror.

3. An object is placed at 10 cm from a concave mirror with a radius of curvature of 30
cm.
(a) Determine the focal length.
(b) Calculate the position of image for that object.
(c) Determine the magnification.
(d) State the characteristics of that image.

4. An object is placed at a distance of 30 cm in front of a curve mirror. If a virtual image
is formed at a distance of 5 cm from the mirror,
(a) calculate the focal length.
(b) calculate the radius of curvature.
(c) state the type of mirror.

5. A spherical mirror produces a virtual image with a linear magnification of 2. If the
object is placed 10 cm from the mirror,
(a) calculate the image distance.
(b) calculate the focal length of mirror.
(c) identify the type of mirror.

6. An object is placed 30 cm from a 15 cm focal length converging lens.
(a) Determine the image distance.
(b) Determine the magnification of the image.
(c) Sketch a ray diagram to show the formation of the image.
(d) State the characteristics of the image formed.

7. An insect of 1.5 cm tall is at 13.0 cm from a converging lens with a focal length of
13.5 cm.
(a) Determine the image distance.
(b) Determine the magnification.
(c) Determine the height of the image produced.
(d) State the characteristics of the image formed.

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8. A converging lens forms a real image of a real object. The image is twice the size of

the object and is formed 90 cm from the lens.

(a) Calculate the object distance.
(b) Calculate the focal length of the lens.
(c) How far the object from the lens if the image is same size as the object?

9. An object is located 20.0 cm to the left of a diverging lens having a focal length f of
32.0 cm.
(a) Calculate the location of the image.
(b) Calculate magnification of the image.
(c) Sketch a ray diagram to show the formation of the image.

10. An object is placed 30 cm to the left of a diverging lens of focal length 20 cm. What
is the location of the image formed?

ANSWERS:

1. (a) 0.091 (b) -0.53 m (c) -0.58 m (d) -1.16 m

2. (c) 10 cm (d) 15 cm

3. (a) 15 cm (b) -30 cm (c) 3

4. (a) -6 cm (b) -12 cm

5. (a) -20 cm (b) 20 cm

6. (a) 30 cm (b) -1

7. (a) -351 cm (b) 27 (c) 40.5 cm

8. (a) 45 cm (b) 30 cm (c) 60 cm

9. (a) -21.31 cm (b) 0.62
10. (a) -12 cm

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TOPIC 7
PHYSICAL OPTICS
7.1 Huygen’s principle
a) State Huygen’s principle (eg. spherical and plane wave fronts).

7.2 Constructive and destructive interferences
a) Define interference of light.
b) Define coherence.
c) State the conditions for interference of light
d) State the conditions of constructive and destructive interference for in phase
and anti-phase sources
*Emphasize on the path difference and its equivalence to phase difference.

7.3 Interference of transmitted light through double- slits
a) Use:
i. for bright fringes (maxima)
m
=
ii. for dark fringes (minima),
1
= (m + 2)

where = 0, ±1, ±2, ±3, . . ..

*Bright fringes:
m=0, central or 0th order max
m=1, first bright or 1st order max

*Dark fringes:
m=0, first dark or 0th order min
m=1, 2nd dark or 1st order min

b) Use =



c) Explain the effect of changing any of the variables.
* : separation between two consecutive dark or bright fringes.

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OBJECTIVE QUESTIONS

(C2, PLO 1, MQF LOD 1)

1. Whose principle or law states that each point on a wave front may be considered a

new wave source?

A. Snell's Law
B. Huygens’s Principle
C. Young's Law

D. Hertz's Law

2. Which of the following statement is TRUE concerning two monochromatic light
waves that are coherent?
A. They have same phase.
B. They have constructive disturbances.
C. They have almost the same amplitude.
D. They have a constant phase difference.

3. If a monochromatic wave from one slit of a Young’s double-slit set-up arrives at
certain point on the screen is one wavelength behind the wave from the other slit.
What is observed at that point?
A. dark fringe.
B. bright fringe.
C. multi-colored fringe.
D. grey fringe.

4. Interference of light is evidence that:
A. The speed of light is very large
B. Light is a transverse wave
C. Light is electromagnetic in character
D. Light is a wave phenomenon

5. In a Young's double-slit experiment, the slit separation is doubled. To maintain the

same fringe spacing on the screen, the screen-to-slit distance D must be changed

to:

A. D/2 B. D /√2

C. D√2 D. 2D

ANSWERS:
1. B 2. D 3. B 4. D 5. D

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STRUCTURED QUESTIONS

(C3, PLO 4, CTPS 3, MQF LOD 6)

1. Two narrow slits are 0.025 mm apart. When a laser shines on them, bright fringes
form on a screen that is a meter away. These fringes are 3.0 cm apart. What is the
separation between the second order bright fringe and the central fringe?

2. A student uses a laser and a double-slit apparatus to project a two-point source
light interference pattern onto a whiteboard located 5.87 m away. The distance
measured between the central bright band and the fourth bright band is 8.21 cm.
The slits are separated by a distance of 0.150 mm. What would be the measured
wavelength of light?

3. In a Young’s double slit experiment the distance between the screen and the slits is
2.0 m. The distance between the center of the interference pattern and tenth bright
fringe is 3.4 cm. If the wavelength of the light used is 5.0 x 10−7 m, determine the
slit separation.

4. A non-monochromatic light source that has two wavelengths; 1 = 450 nm and
2 = 656 nm is used in a Young’s double slits experiment. The slits separation d =

0.5 mm and the screen is located 1.2 m behind the slits. Determine
(a) The position of the first bright fringe for the two wavelengths.
(b) The position of the first dark fringe for the two wavelengths.

5. Given the distance between two slits is 0.10 mm and located 1.2 m from the
screen. Calculate the wavelength used if the second order bright fringe is 1.41 cm
from the center line.

6. In a Young’s double slit experiment, the slits with separation of 0.1 mm, produce
bright and dark fringes on a screen at 20 cm from the slit. If the distance between
the 5th and 7th bright fringe is 2.56 mm, what is the wavelength of the light that is
used?

7. A laser is used to produced Young’s fringes with slits separated by 0.8 mm. the
screen is 1.2 m from the slits and ten fringes separations occupy 13.0 mm.
Calculate
(a) The separation between two bright fringes.
(b) The wavelength of the laser light.

8. Two narrow, parallel slits separated by 0.250 mm are illuminated by green light
(λ = 546.1 nm). The interference pattern is observed on a screen 1.20 m away from

the plane of the slits. Calculate the distance from the central maximum to the first

bright region on either side of the central maximum.

9. Distance between slits and screens are 13.7m apart. A third order fringe is seen on
the screen 2.50cm from the central fringe. If the distance between the two slits
were 0.0960 cm, determine the wavelength of this light. Roughly what color is it?

34

10. In a Young’s double slit experiment, the separation of slits is 0.05 cm and the
distance between the slits and the screen is 200 cm. When a blue light is used, the
distance between the center of the interference pattern with the first bright fringe is
0.13 cm
(a) Calculate the wavelength of the blue light used
(b) Calculate the distance between the center of the interference pattern with the
fourth dark fringe.

Extra Information

Range for visible light wavelength: 700 nm – 400 nm

Red : 780 nm – 622 nm
Orange : 622 nm – 597 nm
Yellow : 597 nm – 577 nm
Green : 577 nm – 492 nm
Blue : 492 nm – 455 nm
Violet : 455 nm – 390 nm

ANSWERS: (b) 5.4 × 10−4 m, 7.87 × 10−4 m
(b) 8.67x10-7 m
1. 6.0 cm (b) 4.55x10-3 m
2. 5.24 x 10-5 cm
3. 2.94 × 10−4 m
4. (a) 1.08 × 10−3 m, 1.57 × 10−3 m
5. 587.5 nm
6. 640 nm
7. (a) 1.3x10-3 m
8. 2.62 x 10 -3 m
9. = 584 yellow light
10. (a) 3.25x10-7 m

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