Aweightlifter deadlifts a 300 kg weight. if the weightlifter has a mass of 100 kg, what is the force acting on his legs?

3920 N

Explanation:

The force acting on his legs is equal to the resultant total force on his body I.e his weight plus the mass he's carrying.

M = m1 + m2

M1 = mass of the weight lifter

M2 = mass of the weight he's carrying

M = sum of the total mass acting on body

M = (100 + 300) kg

M = 400kg

But force = mass * acceleration due to gravity,

Force (f) = 400 * 9.8

F = 3920N

it takes about 30 days for it to break down

c. magnitude and direction