A shell of mass 0.020 kg is fired by a gun of mass 100 kg . If the muzzle speed of the shell is 80ms-1. What is the recoil speed of gun.
15 cm-1
1.6 cms-1
1.9 cms-1
2 cms-1
A stream of water flowing horizontally with a speed of 15ms-1 gushes out of a tube of cross sectional area 10-2m2 and hits a vertical wall nearby. What is the force exerted on the wall by the impact of water, assuming it does not rebound?
2 × 103 N
6 × 103 N
2.25 × 103N
zero
A constant retarding force of 50N is applied to a body of mass 20 kg moving initially with a speed of 15ms-1. How long does the body take to stop?
6 s
10 s
12 s
18 s
A bat man hits back a small straight in the direction of the bowler without changing its initial speed of 12ms-1 of the mass of the ball is 0.15kg determine the impulse impacted to the ball.
3 Ns
3.2 Ns
5 Ns
3.6 Ns
A bullet of mass 0.04 kg moving with a speed of 90ms-1 enters a heavy wooden block and is stopped after a distance of 60cm. What is the average resistive force exerted by the block on the bullet?
250N
260N
270N
300N
When the glass vessels fall on a hard floor they break, but they do not break when the fall on a carpet or sand. Which law is used?
Newton's 1st law
Newton's 2nd law
Newton's 3rd law
law of conservation of momentum
Write relationship between force, mass and acceleration
F = ma
F = ma2
If an elevator is moving vertically up with an acceleration a, the force exerted on the floor by a passenger of mass M is
Ma
M(g + a)
M(g - a)
Zero
