Question

A 60 kg man moved 25 steps up in 25 s. Find the power if each step is 16 cm high. Take the g=10ms-²​

Answer 1

Given :

A 60kg man moved 25 steps up in 25s. Height of each step is 16cm or 0.16m

To Find :

Power of the man.

Solution :

❖ We know that power is defined as the rate of work done per unit time$.$

Mathematically, P = W / t

• P denotes power
• W denotes work done
• t denotes time

First of all we need to find work done by man.

➙ W = F • d

• Here only force due to gravity acts on body which is equal to mg.

➙ W = mgd

➙ W = mg × nh

• n denotes number of steps
• h denotes height of each step

➙ W = 60 × 10 × 25 × 0.16

➙ W = 2400 J

Now let's calculate power!

➠ Power = Work / Time

➠ P = 2400/25

➠ P = 96 W

Answer 2

Given :

A 60kg man moved 25 steps up in 25s. Height of each step is 16cm or 0.16m

To Find :

Power of the man.

Solution :

❖ We know that power is defined as the rate of work done per unit time$.$

Mathematically, P = W / t

P denotes power

W denotes work done

t denotes time

First of all we need to find work done by man.

➙ W = F • d

Here only force due to gravity acts on body which is equal to mg.

➙ W = mgd

➙ W = mg × nh

n denotes number of steps

h denotes height of each step

➙ W = 60 × 10 × 25 × 0.16

➙ W = 2400 J

Now let's calculate power!

➠ Power = Work / Time

➠ P = 2400/25

➠ P = 96 W