Physics Past Questions and Answers

A ball of mass 0.1kg is thrown vertically upwards with a speed of 10ms-1 from the top of a tower 10m high. Neglecting air resistance, its total energy just before hitting the ground is
(take g = 10ms-2)

A 5 J
B 10 J
C 15 J
D 20 J

Question 7:

A car of mass 800kg attains a speed of 25m/s in 20 secs. The power developed in the engine is

A 1 . 25 x 10⁴ W
B 2 . 50 x 10⁴ W
C 1 . 25 x 10⁶W
D 2 . 50 x 10⁶ W

Question 8:

When the brakes in a car are applied, the frictional force force on the tyres is

A Is a disadvantage because it is in the direction of the motion of the car
B Is a disadvantage because it is in the opposite direction of the motion of the car
C Is an advantage because it is in the direction of the motion of the car
D Is an advantage because it is in the opposite direction of the motion of the car

Question 9:

If the stress on a wire is 10⁷NM^-2 and the wire is stretched from its original length of 10.00 cm to 10.05 cm. The young's modulus of the wire is

A 5 . 0 x 10⁴ Nm^-2
B 5 . 0 x 10⁵ Nm^-2
C 2 . 0 x 10⁸ Nm^-2
D 2 . 0 x 10⁹ Nm^-2

Question 10:

A solid weigh 10 .00 N in air, 6 N when fully immersed in water and 7 . 0 N when fully immersed in a liquid X. Calculate the relative density of the liquid, X.

A 5/3
B 4/3
C 3/4
D 7/10