A force is applied on a body of mass 20 kg moving with a velocity of 40 ms-1. The body attains a velocity of 50 ms-1 in 2 seconds. Calculate the work done by the body.
Answers
ANSWER = 9000 J
mass of body = 20 kg
Initial velocity
Of the body = 40 m/s
Final velocity
Of the body = 50 m/s
Time taken = 2 s
Acceleration = v - u / t
Where v is the final velocity , u is the initial velocity and t is time taken
Acceleration = 50 - 40 / 2
= 10 / 2
= 5 m/s^2
According
To 2nd law , F = ma
Where F is force m is mass of body and a is it's acceleration
F = 20 × 5
= 100 N
According to equations of motion,
s = ut + 1/2 at^2
Where s is displacement ,u is initial velocity , v is final velocity a is acceleration and t is time taken
s = (40 × 2) + 1/2 ( 5 × 4)
= 80 + 10
= 90 m
Work done = Force × displacement
= 100 × 90
= 9000 J
Explanation:
Atoms don't age. Atoms radioactively decay when a lower-energy nuclear configuration exists to which they can transition. The actual decay event of an individual atom happens randomly and is not the result of the atom getting old or changing through time.