An immersion heater of 400 watts kept on for 5 hours will consume electrical power of?
Correct answer: A. 2 kWh
- A. 2 kWh
- B. 20 kWh
- C. 6 kWh
- D. 12 kWh
Explanation
To calculate the electrical power consumed by the immersion heater, you can use the formula: Power (P) = Voltage (V) × Current (I) Given that the heater's power rating is 400 watts, and assuming it operates at the standard household voltage of 220 volts: Power (P) = 400 watts Voltage (V) = 220 volts Now, we need to calculate the current (I) using Ohm's Law: Current (I) = Power (P) / Voltage (V) Current (I) = 400 watts / 220 volts Once we have the current, we can calculate the total electrical energy consumed using the formula: Energy (E) = Power (P) × Time (t) Given that the heater is kept on for 5 hours: Energy (E) = 400 watts × 5 hours Now, plug in the values and calculate: Current (I) = 400 watts / 220 volts ≈ 1.818 Amperes Energy (E) = 400 watts × 5 hours = 2000 watt-hours (Wh) or 2 kilowatt-hours (kWh) So, the immersion heater will consume electrical power of 2 kilowatt-hours (kWh) when kept on for 5 hours.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Current Electricity
Steady current relates charge flow to potential difference, resistance and resistivity, including how temperature changes a conductor's resistance. Sources with internal resistance have terminal voltage below their emf when delivering current, and maximum power output occurs under a specific load condition rather than at zero resistance.
Practise Current Electricity
1,052 free Current Electricity MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Physics questions like this
Physics is on 16 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Current Electricity questions
If a certain piece of copper is to be shaped into a conductor of minimum resistance, it is length (L) and cross-sectional area (a) shall respectively be :
In a parallel circuit, the voltage remains the _.
The resistivity of a wire is _ ohm-m if 0.75 A current flows through it by applying 1.5 V potential difference, take length and cross-sectional area as 5m and 2.5 x 10^-7 m^2.
If the length of a potentiometer wire is doubled, the accuracy in determining the null point _.
Calculate the work done in a resistor of 20 ohm carrying 5A of current in 3 hours.
A potentiometer is used to measure the emf of a cell. At null point, no current flows through _.