Question

A man exerts a force of 200N in pulling a cart at a constant speed of 16m/s. Calculate the power spent by man

Answer 1

Given:

The force exerted by the man to pull the cart = 200 N

The speed of the cart = 16 m/s

To find:

The power spent by the man.

Solution:

We know that the formula of power in terms of velocity is:

Power = Force × velocity

On substituting the values in the formula, we get:

Power = 200×16

= 3200 N·m/s

Thus the power spent by the man will be 3200 N·m/s.

Answer 2

POWER EXERTED IS 3.2 KILOWATT.

Given:

• Force exerted = 200 N
• Velocity of cart = 16 m/s

To find:

Power spent by man ?

Calculation:

Power is the instàntaneous work done by a force with respect to time.

• Let power be P :

$P = \dfrac{work}{time}$

$\implies P = \dfrac{force \times d}{time}$

• 'd' is Displacement

$\implies P = force \times \dfrac{ d}{time}$

$\implies P = force \times velocity$

$\implies P = 200 \times 16$

$\implies P = 3200 \: watt$

$\implies P = 3.2 \: kilowatt$

So, power dissipated is 3.2 kilowatt.