| ⇦ | 
| ⇨ |
A wire of a certain material is stretched slowly by ten percent. Its new resistance and specific resistance become respectively
Options
(a) both remain the same
(b) 1.1 times, 1.1 times
(c) 1.2 times, 1.1 times
(d) 1.21 times, same
Correct Answer:
1.21 times, same
Explanation:
Δl / l = 0.1 , Therefore, l = 1.1 but the area also decreases by 0.1.
mass = ρlA = Vρ. In l + In A = 1n mass.
.·. Δl / l = ΔA / A = 0 ⇒ Δl / l = -ΔA / A
Length increases by 0.1, resistance increases, area decreases by 0.1, then also resistance will increase. Total increase in resistance is approximately 1.2 times, due to increase in length and decrease in area. But specific resistance does not change.
Related Questions: - The maximum and minimum magnitudes of the resultant of two vectors
- An inductor 20 mH, a capacitor 50 μF and a resistor 40Ω are connected in series
- Which phenomenon best supports the theory that matter has a wave nature?
- A particle falls towards earth from infinity. Its velocity on reaching the earth
- A liquid boils when its vapour pressure equals
Topics: Current Electricity
(136)
Subject: Physics
(2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
- The maximum and minimum magnitudes of the resultant of two vectors
- An inductor 20 mH, a capacitor 50 μF and a resistor 40Ω are connected in series
- Which phenomenon best supports the theory that matter has a wave nature?
- A particle falls towards earth from infinity. Its velocity on reaching the earth
- A liquid boils when its vapour pressure equals
Topics: Current Electricity (136)
Subject: Physics (2479)
Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score
18000+ students are using NEETLab to improve their score. What about you?
Solve Previous Year MCQs, Mock Tests, Topicwise Practice Tests, Identify Weak Topics, Formula Flash cards and much more is available in NEETLab Android App to improve your NEET score.
Share this page with your friends
Leave a Reply