Question

1) If one or two persons give a sudden push to a car with a dead battery, it hardly starts. But a continuous push over some time results in gradual acceleration. This is an example of *
a)Newton’s first law
b)Newton’s second law
c)Newton’s third law
d)Law of conservation of momentum

2) The value of constant force that is applied for 1 s on a 10 Kg object to increase its velocity from 5 m/s to 10 m/s is *
1 point
a)2 N
b)20 N
c)500 N
d)50 N

Answer 1

Answer:

1) (b) Newton's second law of motion

1)(d) 50 N

Explanation:

1) If you give sudden push then time will be less, let's say 0.5 s the force rquired will increase as time is inversely proportional to force.

We used the formula,

F=m(v-u)/t

2) By using the same formula Force = Rate of change in momentum (By second law of motion)

m= 10kg

v=10m/s

u= 5m/s

t= 1 s

F = m(v-u)/t

F = 10(10-5)/1

F= 50 N