Define (a) Energy (b) power
Answers
Answer:
The ability to do work is called energy ,The strength to do work is called power
Answer:
Energy, in physics, the capacity for doing work. It may exist in potential, kinetic, thermal, electrical, chemical, nuclear, or other various forms. There are, moreover, heat and work—i.e., energy in the process of transfer from one body to another. After it has been transferred, energy is always designated according to its nature. Hence, heat transferred may become thermal energy, while work done may manifest itself in the form of mechanical energy.
Explanation:
Power is the rate with respect to time at which work is done; it is the time derivative of work:
{\displaystyle P={\frac {dW}{dt}}}{\displaystyle P={\frac {dW}{dt}}}
where P is power, W is work, and t is time.
If a constant force F is applied throughout a distance x, the work done is defined as {\displaystyle W=\mathbf {F} \cdot \mathbf {x} }{\displaystyle W=\mathbf {F} \cdot \mathbf {x} }. In this case, power can be written as:
{\displaystyle P={\frac {dW}{dt}}={\frac {d}{dt}}\left(\mathbf {F} \cdot \mathbf {x} \right)=\mathbf {F} \cdot {\frac {d\mathbf {x} }{dt}}=\mathbf {F} \cdot \mathbf {v} }{\displaystyle P={\frac {dW}{dt}}={\frac {d}{dt}}\left(\mathbf {F} \cdot \mathbf {x} \right)=\mathbf {F} \cdot {\frac {d\mathbf {x} }{dt}}=\mathbf {F} \cdot \mathbf {v} }
If instead the force is variable over a three-dimensional curve C, then the work is expressed in terms of the line integral:
{\displaystyle W=\int _{C}\mathbf {F} \cdot d\mathbf {r} =\int _{\Delta t}\mathbf {F} \cdot {\frac {d\mathbf {r} }{dt}}\ dt=\int _{\Delta t}\mathbf {F} \cdot \mathbf {v} \ dt}{\displaystyle W=\int _{C}\mathbf {F} \cdot d\mathbf {r} =\int _{\Delta t}\mathbf {F} \cdot {\frac {d\mathbf {r} }{dt}}\ dt=\int _{\Delta t}\mathbf {F} \cdot \mathbf {v} \ dt}
From the fundamental theorem of calculus, we know that {\displaystyle P={\frac {dW}{dt}}={\frac