Question

If a machine does work at the rate of 0.5
joules in every two seconds, then its power
is said to be:
(A) 1 watt
(B) 4 watts
(C) 0.5 watt
(D) 0.25 watt​

Answer 1

Answer:

Electrical Energy and Power

Electrical Energy supplies the power required to produce work or an action within an electrical circuit and is given in joules per second

Electrical Energy is the ability of an electrical circuit to produce work by creating an action. This action can take many forms, such as thermal, electromagnetic, mechanical, electrical, etc. Electrical energy can be both created from batteries, generators, dynamos, and photovoltaics, etc. or stored for future use using fuel cells, batteries, capacitors or magnetic fields, etc. Thus electrical energy can be either created or stored.

We remember from our school science classes that the “The Law of the Conservation of Energy” states that energy cannot be created or destroyed, only converted. But for energy to do any useful work it must be converted from one form into something else. For example, a motor converts electrical energy into mechanical or kinetic (rotational) energy, while a generator converts kinetic energy back into electrical energy to power a circuit.

Answer 2

Answer:

Data: Work=0.5 J, Time= 2 seconds, power=?

Solution: P=W/t =0.5/2=0.25watt.