WorksheetsUnderstanding Electrical Power and Energy
Total questions: 10
Worksheet time: 8mins
What is the SI unit of electrical power? A) Joule (J) B) Volt (V) C) Watt (W) D) Ampere (A)
Coulomb (C)
Ohm (Ω)
Farad (F)
C) Watt (W)
What is the formula for calculating electrical power (P) in a direct current circuit? A) P = V · I B) P = V / I C) P = I / V D) P = R · I
P = V + I
P = R / I
A) P = V · I
P = I · R
The electrical energy (W) consumed by a device is given by which formula? A) W = P / t B) W = P · t C) W = V · R D) W = I · t
W = P + t
B) W = P · t
W = I · R
W = V / R
Which of the following is a unit of electrical energy used by utility companies? A) Watt (W) B) Horsepower (HP) C) Kilowatt-hour (kWh) D) Ohm (Ω)
G) Volt (V)
E) Joule (J)
C) Kilowatt-hour (kWh)
F) Ampere (A)
If we double the voltage (V) across a resistor while keeping the resistance constant, what happens to the power (P)? A) Stays the same B) Doubles C) Quadruples D) Halves
B) Triples
A) Increases
C) Quadruples
D) Reduces by a quarter
How many Watts (W) are in 1 horsepower (1 HP)? A) 100 W B) 500 W C) 746 W D) 1000 W
B) 650 W
D) 1200 W
C) 746 W
A) 300 W
A device rated at 2000W operates for 2 hours. How much energy did it consume in kWh? A) 1 kWh B) 2 kWh C) 4 kWh D) 4000 kWh
3 kWh
5 kWh
C) 4 kWh
0.5 kWh
What is the relationship between voltage, current, and resistance in an electrical circuit? A) Ohm's Law B) Kirchhoff's Law C) Faraday's Law D) Coulomb's Law
E) Newton's Law
F) Ampere's Law
G) Joule's Law
A) Ohm's Law
What happens to the current (I) in a circuit if the resistance (R) is increased while the voltage (V) remains constant? A) Increases B) Decreases C) Stays the same D) Fluctuates
B) Decreases
Increases rapidly
Remains constant
Decreases slightly
Which of the following devices typically consumes the most electrical power? A) LED bulb B) Refrigerator C) Laptop D) Smartphone charger
C) Desktop computer
B) Refrigerator
D) Hair dryer
A) Electric kettle
