1. Sound of Music Learning check! #5

2. 1.Which lens would make the best magnifying glass ? A. Diverging, long focal length B. Converging, long focal length C. Diverging short focal length D. Converging, short focal length

3. 2.Real is positive means A. Diverging lenses have negative focal lengths B. Diverging lenses never produce real images C. Converging lenses always produce real images D. Converging lenses only produce real images from close up objects

4. 3. 1/u + 1/v = 1/f A. u = image distance B. v =object distance C. v = image distance D. f = u + v

5. 4.Which does NOT apply to the power of a lens A. Measured in m -1 B. 1/f C. Measured in DD. Always positive

6. 5.A diverging lens CAN produce a real image if A. It has a high power B. The object is virtual C. The object is closer than the focal length D. The image is diminished

7. 6.u =4cm, v = 6cm, f =? A. 2.4cm B. 5cm C. 3cmD. 10cm

8. 7.u=3cm, v=-4cm, f= ? A. 0.83cm B. 12cm C. –12cmD. –0.83cm

9. 8.The lens formula applies to A. Thin mirrors B. All lenses C. Thin lensesD. Octopus eyes

10. 9.This object is placed 4cm from a converging lens of focal length 6cm. Its image is A. B. C. D.

11. 10.Your favourite physics teacher’s eyesight has deteriorated from –2.25D to –2.50D in 5 years. What is the rate of change of focal length in mmyr - 1 ? A.-0.0089 B 11.25 C. 0.0089D. 1.25

12. 11.Which has the longest focal length? A. Diverging lens, red light B. Converging, lens blue light C. Diverging lens blue light D. Converging, lens red light

13. 12.Penguin eyes are more powerful A. On land B. In water C. In spaceD. In a pile of fish guts Think – more powerful means f has decreased

14. 1.Which lens would make the best magnifying glass ? A. Diverging, long focal length B. Converging, long focal length C. Diverging short focal length D. Converging, short focal length

15. 2.Real is positive means A. Diverging lenses have negative focal lengths B. Diverging lenses never produce real images C. Converging lenses always produce real images D. Converging lenses only produce real images from close up objects

16. 3. 1/u + 1/v = 1/f A. u = image distance B. v =object distance C. v = image distance D. f = u + v

17. 4.Which does NOT apply to the power of a lens A. Measured in m -1 B. 1/f C. Measured in DD. Always positive

18. 5.A diverging lens CAN produce a real image if A. It has a high power B. The object is virtual C. The object is closer than the focal length D. The image is diminished

19. 6.u =4cm, v = 6cm, f =? A. 2.4cm B. 5cm C. 3cmD. 10cm

20. 7.u=3cm, v=-4cm, f= ? A. 0.83cm B. 12cm C. –12cmD. –0.83cm

21. 8.The lens formula applies to A. Thin mirrors B. All lenses C. Thin lensesD. Octopus eyes

22. 9.This object is placed 4cm from a converging lens of focal length 6cm. Its image is A. B. C. D.

23. 10.Your favourite physics teacher’s eyesight has deteriorated from –2.25D to –2.50D in 5 years. What is the rate of change of focal length in mmyr - 1 ? A.-0.0089 B 11.25 C. 0.0089D. 1.25

24. 11.Which has the longest focal length? A. Diverging lens, red light B. Converging, lens blue light C. Diverging lens blue light D. Converging, lens red light

25. 12.Penguin eyes are more powerful A. On land B. In water C. In spaceD. In a pile of fish guts Think – more powerful means f has decreased For the best refraction you want the biggest difference refractive index C. In space