Question

Show that 480 W of power is expended by a weightlifter
when lifting a 60-kg barbell a vertical distance of 1.2 m
in a time interval of 1.5 s.

Answer 1

Answer on Question#39462 - Physics, Mechanics | Kinematics | Dynamics

Show that 480 W of power is expended by a weightlifter when lifting a 60-kg barbell a vertical distance of 1.2 m in a time interval of 1.5 s.

Solution:

Power is the rate at which work is done. It is the work/time ratio. Mathematically, it is computed using the following equation:

$$P = \frac {E}{t} = \frac {F \cdot d}{t} = \frac {mg \cdot d}{t} = \frac {60kg \cdot 10 \frac {N}{kg} \cdot 1.2m}{1.5s} = 480W$$