10 Question-answer on resistance
1. The length of a conductor is halved, its conductivity will be:
(a) Doubled
(b) Halved
(c) Quadrupled
(d) Unchanged
Ans: (d)
2. The length of a conductor is doubled. Its conductance will be:
(a) Unchanged
(b) Halved
(c) Doubled
(d) Quadrupled
Ans: ( b)
3. The length and area of cross-section of a conductance are doubled its resistance is:
(a) Unchanged
(b) Halved
(c) Doubled
(d) Quadrupled
Ans: (a)
4. The length of a conductor is doubled and its radius is halved, its specific resistance is
(a) Unchanged
(b) Halved
(c) Doubled
(d) Quadrupled
Ans: (a)
5. The length of a conductor is doubled and its radius is halved, its resistance is:
(a) Unchanged
(b) Doubled
(c) Quadrupled
(d) Eight times its value
Ans: (d)
6. Conductivity of a conductor depends upon
(a) Length
(b) Area of cross-section
(c) Volume
(d) temperature
7. a square aluminum rod is 1 m long and 5 mn on edge. What must be the radius of another aluminum rod whose length 1 m and which has the same resistance as the previous rod.
(a) 5 mm
(b) 4.2 mm
(c) 2.8 mm
(d) 1.4 mm
Ans: ( c)
8. A given piece of wire of length l cross-sectional area A, and resistance R is stretched uniformly to a wire of length 2l. the new resistance is:
(a) R/2
(b) R
(c) 2R
(d) 4R
Ans: ( d)
9. The example of a non-ohmic resistance is:
(a) Diode
(b) Copper wire
(c) Filament lamp
(d) Carbon resistor
Ans: ( a)
10. Which of the following has negative temperature coefficient of resistance?
(a) Platinum
(b) Tungsten
(c) Carbon
(d) Nichrome
Ans: (c)