Jamb Physics 2021 Past Questions and Answers

Question 16:

• JAMB 2021

A lead bullet of mass 0.05kg is fired with a velocity of 200ms${}^{-1}$ into a block of mass 0.95kg. Given that the lead block can move freely, the final kinetic energy after impact is?

A. 50J
B. 100J
C. 150J
D. 200J

Question 17:

• JAMB 2021

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

Question 18:

• JAMB 2021

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

A. 1.25 x 10${}^4$W
B. 2.50x 10${}^4$W
C. 1.25 x 10${}^6$W
D. 2.50 x 10${}^6$W

Question 19:

• JAMB 2021

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

A. A disadvantage because it is in the direction of the motion of the car
B. A disadvantage because it is in the opposite direction of the motion of the car
C. An advantage because it is in the direction of the motion of the car
D. An advantage because it is in the opposite direction of the motion of the car

Question 20:

• JAMB 2021

If the stress on a wire is 10${}^7$NM${}^{-2}$ 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 10${}^{-4}$Nm${}^{-2}$
B. 5.0 x 10${}^{-5}$Nm${}^{-2}$
C. 2.0 x 10${}^{-8}$Nm${}^{-2}$
D. 2.0 x 10${}^9$Nm${}^{-2}$