Question

A man can lift a block of mass of \[50kg\] up to a height of \[2\] m in \[2\] seconds. Calculate the power developed by the man to lift the block.
A. \[10000W\]
B. \[1000W\]
C. \[500W\]
D. \[45W\]
E. \[25W\]

Answer 1

Hint: To solve this question we have to know about the power. We know that power can be characterized as the rate at which work is done for example energy changed over. The unit of power is Watt. We can say, power is an actual idea that has a few distinct implications, contingent upon the unique circumstance and the data that is accessible. We can characterize power as the pace of managing a job. It is the measure of energy devoured per unit time.

Complete step by step answer:
Here in this question the given quantities are,
\[m = 50\,kg\], $m$ is the mass of the block that the man can lift.
\[h = 2m\], $h$ is the height up to which the man can lift the block.
\[t = 2s\], $t$ is the time period.
We know that the formula of work done in lifting the block is, \[W = mgh\]
After putting the values of m , g and h we will get,
\[W = 50 \times 10 \times 2 = 1000J\]
Power developed is, \[P = \dfrac{W}{t}\]
After putting the values of W and t, we will get,
\[P = \dfrac{{1000}}{2} = 500\,W\]
So, the power will be \[500\,W\].

So, the correct answer is option C.

Note:Students can get confused between power and force. The concept of these two is different.Force is a fundamental result of intersection between two objects and power is the expression of energy consumed over time where force is an element.And they can also use wrong units of power and work. The SI unit of force is Joules each Second (J/s), which is named as Watt. Watt can be characterized as the force taken to do one joule of work in one second.