Physics help question 5?

At the 1996 Summer Olympics in Atlanta, Georgia, a mass of 260 kg was lifted for the first time ever in a clean-and-jerk lift. The lift, performed by Russian weightlifter Andrei Chemerkin, earned him the unofficial title as “the world’s strongest man.” If Chemerkin did 6685 J of work in exerting a force of 2949 N, how high did he lift the mass?

1 Answer
Feb 5, 2018

He must have raised the mass 2.62 m. Solution below.

Explanation:

The definition of work is used here. As he lifts the weight, he does work in overcoming the force of gravity.

Since the force he works against is gravity, the work he does gets stored (in the new arrangement of weights and Earth), and so becomes potential energy.

The amount of gravitational potential energy ( and the amount of work he does) can be calculated by

#U=mgh#

Where U is the potential energy (the work done), m is the mass lifted, g is the strength of the gravitational field (9.8 N/kg) and h is the height lifted.

Using our values,

#6685 J = 260 kg xx 9.8 N/(kg)xxh#

#h = (6685)/(260xx9.8)=2.62 m#