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 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
The acceleration produced in a body by a force of given magnitude depends on
size of body
shape of body
mass of body
none of body
A body of mass 10kg moving with a velocity 20ms-1 along a straight line collides with another body of mass 8kg moving in the same direction with a velocity 5ms-1. After collision if the velocity of the former is reduced to 16ms-1, Calculate the final velocity of the latter.
10ms-1
15ms-1
25ms-1
0
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
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
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
Write relationship between force, mass and acceleration
F = ma
F = ma2
The motion of rocket is an example for which law.
Law of conservation of momentum.
