Question 4691:

The speed of light in is 3.0x108 m/s. Its speed in glass having a refractive index of 1.65 is ____________

A. \(1.82 x 10^8m/s \)
B. \(3 x 108m/s \)
C. \(6.0 x 108m/s \)
D. \(1.82 x 102m/s \)

Question 4692:

The slope of a straight-line displacement time graph indicates ____________

A. Distance travelled
B. Uniform velocity
C. Uniform acceleration
D. Instant acceleration
E. Uniform speed

Question 4693:

A ball of mass 0.5kg moving at 10m/s collides with another ball of equal mass at rest. If the two balls move off together after the impart, calculate their common velocity

A. 0.2m/s
B. 0.5m/s
C. 10m/s
D. 3m/s

Question 4694:

How much heat is given out when a piece of iron mass 50g and specific heat capacity 460Jkg-1K-1 cools from 85°c to 25°c?

A. 1.38 x 106J
B. 2.53 x 102J
C. 1.98 x 104J
D. 1.38 x 103J
E. 1.27x103J

Question 4695:

Which of the following is not a suitable method of reducing loss of heat from a piece of hot iron?

A. Wrapping it in cotton wool
B. Painting it black
C. Placing it in a vacuum
D. Placing it in a rubber support
E. Keeping it in a closed wooden box