Practical Electricity

Question 1

Define Electrical Power (Scalar), P

Answer 1

It’s the rate of electrical energy converted to other forms of energy

Question 2

SI Unit of Power

Answer 2

W (watt)

Question 3

Formulas of Power (3 formulas)

Answer 3

P = VI = I²R = V²/R

Question 4

One watt is defined as…

Answer 4

the power delivered when one joule of energy is converted in one second.

Question 5

Electrical Energy is a scalar quantity with its symbol being E.

Express the 4 formulas for calculating energy in terms of I (current), R (resistance), V (potential difference) and t (time).

Answer 5

E=Pt, E=VIt, E=I²Rt, E=V²t/R

Question 6

SI Unit of Electrical Energy

Answer 6

J (joule)

Question 7

One kWh is defined as…

Answer 7

the amount of electrical energy used by a 1 kW device in one hour.