Question

A force of 100N stops a body moving with a velocity of 20 m/s . The force required to stop the same body when moving 30 m/s in the same distance is

Answer 1

f=ma

100 N=m×20

100N÷20=m

m=5kg

f=ma

f=(5×30)

f=150N

the force required is 150N

Answer 2

Answer:

225N

Explanation:

GIVEN:

F1=100N

V1=20m/s

V2=30m/s

Mass and distance are constants

TO FIND:

F2

SOLUTION:

F1=m v1/t1

F1 * t1/v1=m........(1st eqn)

F2=m v2/t2

F2 * t2/v2=m........(2nd eqn)

from eqns 1 and 2, we get

F1 * t1/v1=F2 * t2/v2

F1 * s/v1 * v1=F2 * s/v2 * v2                             (as t=s/v)

as s is constant, we get

F1/v1 * v1= F2/v2 * v2

By substituting all its values, we get

100/20 * 20= F2/30 * 30

225N=F2

Hope it helpss...