The resistance of a wire is 1Ω. Which of the following is new resistance if length of wire is doubled?
Correct answer: A. 2 Ω
- A. 2 Ω
- B. 4 Ω
- C. 1/2 Ω
- D. 1/4 Ω
Explanation
R = pL / A If p (resistivity) and A (area) remain the same, then R ∝ L As L doubles, R will also double. So, R' = 2R R' = 2 Ω
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
1,053 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
When a wire is stretched double of is length, then its resistance will be
Which of the following have the same temperature coefficient of resistivity?
Which 100cm long and 2.0 mm diameter has a resistance of 0.7 ohm, the electrical resistivity of the material is
When Cu and Ge are cooled to -150 oC Then resistance of Cu _ and that of Ge _
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?
Internal resistance of ideal current source is: