Question

Two coolies $A$ and $B$ do some work in time 1 minute and 2 minute respectively.The power spent is
A. same by both coolie
B. is more by coolie $A$ than by $B$
C. is less by coolie $A$ than by $B$
D. nothing can be said

Answer 1

Hint:We know that Power is inversely proportional to time. If a force has a component that is opposite the direction of displacement at the point of application, it produces negative work.

Complete step by step answer:
Electric power is the rate at which electrical energy is transmitted by an electric circuit per unit of time. The watt, or one joule per second, is the SI unit of power. Electric generators are the most common source of electricity, however other sources such as electric batteries can also be used.

The electric power sector often provides it to companies and residences (as residential mains electricity) via an electric power grid. Transmission lines can transport electric power across vast distances and be utilised for high-efficiency applications including motion, light, and heat. Work is the energy delivered to or from an item by applying force along a displacement in physics.

It is frequently expressed as the product of force and displacement in its simplest form. When applied, a force is said to produce positive work if it has a component in the direction of the point of application's displacement. A and B, two coolies, do some work in 1 minute and 2 minutes, respectively.
${\mathbf{P}} = \dfrac{{\mathbf{W}}}{{\mathbf{t}}}$
$\Rightarrow {\mathbf{P}} \propto \dfrac{{\mathbf{1}}}{{\mathbf{t}}}$
$\Rightarrow {{\mathbf{t}}_{\text{A}}} < {{\mathbf{t}}_{\text{B}}}$
$ \therefore {{\mathbf{P}}_{\text{A}}} > {{\mathbf{P}}_{\text{B}}}$
The power spent is more by coolies A than by B.

Hence, the correct answer is option B.

Note:Make sure you follow the correct unit conversions. Work and energy are inextricably linked. According to the work–energy principle, an increase in the kinetic energy of a rigid body is generated by an equivalent amount of positive work done on the body by the force acting on it. A reduction in kinetic energy is generated by the resulting force doing an equivalent amount of negative work. As a result, if the net work is positive, the particle's kinetic energy increases by the same amount. If the total work done is negative, the particle's kinetic energy is reduced by the same amount.