Question

a body of mass 40kg is moving in a straight line on a smooth horizontal surface. its velocity decreases from 5.0 m/s to 2.0 m/s in 6 seconds. find the force acting on his body. how much distance would it travel during this time

Answer 1

here is your answer

given :

mass = 40 kg

initial velocity (u) = 5 m/s

final velocity (v) = 2 m/s

time taken (t) = 6 seconds

to find : force acting on the body & distance travelled

solution :

acceleration = change in velocity / time taken

acceleration = (v-u)/t

acceleration = (2-5)/6

acceleration = -0.5

so, force = mass*acceleration

force = 40*(-0.5)

force = -20 Newton

now, by using 3rd equation of motion

v^2 = u^2+2as

(2)^2 = (5)^2+2*(-0.5)*s

4-25 = -1s

s = 21 meter

so, force acting on the body is -20 Newton and distance travelled by the body in 6 seconds is 21 meter.