Question

Question 30:
For how long should a force of 100 N act on a body of 20 kg so that it acquires a velocity of 100 m/s ?

Lakhmir Singh Physics Class 9

Answer 1

F = ma
m = 20
F = 100
a= v-u / t
F = m × ( v-u)/t
v = 100
u=0
F = 20 × (100-0)/t
100 = 2000/ t
100t = 2000
t= 2000/100
t = 20 seconds