Physics Past Questions and Answers

An object is placed in front of a concave mirror whose radius of curvature is 12cm. If the magnification of the Image produced is 1.5, how far is the object from the mirror?

A 8cm
B 10cm
C 15cm
D 18cm
E 20cm

Question 252:

A body moves along a circular path with uniform angular speed of 0.6 rad s^-1 and at a constant speed of 3.0 ms^-1.

Calculate the acceleration of the body towards the centre of the circle.

A 0.2.ms^-2
B 1.8 ms^-2
C 5.0 ms^-2
D 5.4 ms^-2
E 25.0 ms^-2

Question 253:

Which of the statements is/are true of two bodies involved in an inelastic collision? After collision.

I. the kinetic energy increases
II. The momentum decreases
III. Their velocities are the same.

A I only
B II Only
C III only
D I and II only
E II and III only

Question 254:

491 K is equivalent to ____________

A 273 °C
B 218 °C
C 373 °C
D 491 °C
E 764 °C

Question 255:

An atom radiates 1.5 × 10^-19J when an electron jumps from one level to another. What is the wavelength of the emitted radiation? (Planck’s constant 6.6 × l0^-34Js ; Speed of light in vacuum = 3.0 × 108ms^-1)

A 1.32 × 10^-6m
B 2.97 × 10^-6m
C 3.30 × 10^-6m
D 6.82 × 10^-6m
E 8.01 × 10m^-6