Question

10. A body of mass 5 kg is at rest on a
smooth horizontal surface. A horizontal
force 'F' acts on it for 4s and then ceases to
act. If the body travels 40 m in the next 5s,
the value of F is,
1) 5 N 2) 20 N 3) 15 N 4) 10 N​

Answer 1

Answer:

10 N

Explanation:

F=ma

a=F/5(for first 4 sec)

v=u+at

u=0

v=4F/5

after this velocity is constant

v=x/t

4F/5=40/5

so F=10N