Question

a 70 kg man runs up the stairs in 4.9 sec . the height of stairs is 5 meters . he will consume power equal to​

Answer 1

✦ Given:-

• Mass of man (m) = 70kg

• Time taken (t) = 4.9s

• Height of stairs (h) = 5m

✦ To Find:-

• Power consume by him.

✦ Solution:-

As we know that Power is defined as the rate of doing work . It means that

→ Power = Workdone/Time taken

here

The acceleration due to gravity is 9.8m/s².

Work done = Maa× Acceleration due to gravity×height/Time taken

✦Power = Mgh/t

substitute the value , we get

→ Power = 70×9.8×5/4.9

→ Power = 3430/4.9

→ Power = 700W

∴ The power consumed by him is 700Watt.