A heater of resistance is connected to a supply. What is the power consumed (in W)?
Answer and explanation
Correct answer: D. 480
- Step 1: The electrical power dissipated by an ohmic heating resistor connected across a steady voltage is given by .
- Step 2: Substitute potential difference and resistance : .
- Step 3: Computing the square and quotient gives .
Answer
480.
Why not the others: 2 calculates current instead of power; 240 halves the power or confuses power with supply voltage; 28800 calculates instead of .
Practise more Current electricity.
Free questions with an explanation for every one, and full timed NEET UG mock tests.
More Current electricity questions
- A heater of resistance is connected to a supply. What is the power consumed (in W)?
- A heater of resistance is connected to a supply. What is the power consumed (in W)?
- A cylindrical copper wire of resistance R is uniformly stretched until its length is doubled (l' = 2l) while keeping its volume constant. Wh…
- Why does the electrical resistivity of metallic conductors increase with rising temperature, whereas the resistivity of intrinsic semiconduc…
- What is the color code sequence on a carbon resistor having a nominal resistance of 47 kΩ ± 10%?
- Two electric bulbs rated 220 V, 40 W and 220 V, 100 W are connected in series across a 220 V power supply. Which bulb will glow brighter, an…