Question

If a weightlifter raises a barbell with 100n of force from the floor over his head(2.5 meters) in 2 seconds. What is the power input?

Answer 1

Power input is 125 W.

Step-by-step explanation:

Given:

Force applied for lifting the barbell,
`F=100\textrm{ N}`

Displacement caused by the force,
`S=2.5\textrm{ m}`

Time taken for the lift,
`t=2\textrm{ s}`

Work done by the weightlifter in raising the barbell is given as,

`Work=Force* displacement\\Work=100* 2.5\\Work=250\textrm{ J}`

Now, power input is given as,

`Power=(Work)/(Time)\\\\Power=(250)/(2)=125\textrm{ W}`

Therefore, the power input is 125 watts.