Power

Question 1

How is work measured in mechanical systems?

Answer 1

Work done is measured in joules (J), where one joule is the amount of work done when a force of one newton (N) moves a mass over a distance of one meter (m) in the direction of the applied force.

Question 2

How is work measured in electrical systems?

Answer 2

Work done is measured in joules (J), where one joule is the amount of work done when a charge of one coulomb (C) is moved through a potential difference of one volt (V).

Question 3

What is potential difference (PD) and how is it measured?

Answer 3

Potential difference is the measure of electrical potential energy available per coulomb of charge, measured in volts (V), where one volt equals one joule per coulomb (J/C).

Question 4

Define power in the context of electrical systems.

Answer 4

Power is the rate at which either work is done or heat is transferred, measured in watts (W) or joules per second (J/s).

Question 5

what are the power formulas?

Answer 5

P=VI
P=I²R
P=V²/R

Question 6

what are the calculations for work?

Answer 6

Work = QxV joules
Q=Ixt
work =VxIt joules

Question 7

How is electrical power measured directly?

Answer 7

Using a wattmeter, which consists of a voltmeter and an ammeter in one housing, providing an indication in watts.

Question 8

How is electrical power measured indirectly?

Answer 8

By measuring voltage and current separately with a voltmeter and an ammeter, and then multiplying the results manually.