8. If you ran up stairs that were 6 m high in 6.5 seconds and you weigh 600N how much power

was used? (in watts and in Horsepower)

553.8 Watts

0.74 Hp

Explanation:

Power is work done per unit time, expressed as

P=W/t

Where P is power, t is time taken and W is work done.

Work is the product of force and perpendicular distance moved hence W=Fd where F is force and d is perpendicular distance.

Substituting W with Fd into the first formula then power is expressed as

P=Fd/t

Substituting F with 600 N, d with 6 m and t with 6.5 seconds then

P=600*6/6.5=553.84615384615 Watts

Rounded off as 553.8W

1 W=0.00134 british horsepower

553.8 W=0.00134*553.8=0.742719926544903597 Hp

Alternatively, we divide the watts by 746 hence 553.8/746=0.7424211177562

Rounding off, power is equal to 0.74 Hp