If the current in electric bulb decreases by 0.5%, the power in the bulb decreases by approximately:
Correct answer: A. 1%
- A. 1%
- B. 0.5%
- C. 2%
- D. 0.25%
Explanation
%age increases in P = 2 (%age increase in 1) → %age increase in P = 2 (0.5%)=1%
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
A new flashlight cell of emf 1.5 volts gives a current of 15 A, when connected directly to a ammeter of resistance 0.04Ω. The internal resistance of cell is:
Internal resistance of ideal current source is:
An 8Ω resistance connected to a battery with internal resistance draws 1.6 A and if a 30Ω resistance is connected to the same battery it draws 0.5A. What is the current drawn by a 6Ω resistance from this battery?
What will be energy used by the battery if the battery has to drive 6.28 x 10^18 electron with potential difference of 20 V across the terminal?
A 100 W, 200V bulb is connected to a 160 V supply. The actual power consumption would be:
You are given four bulbs of 25W, 40W, 50W and 60W. Which bulb has the lowest resistance?