Which of the following rods of same material undergoes maximum elongation when subjected to a given force?
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(a) l=1 m, d=2 mm (b) l=2 m, d=1 mm (c) l=1 m, d=1 mm (d) […]
Water flows through a pipe. The area of cross-section at one place A₁=10 cm², velocity of flows 1 m/s and pressure 2000 Pa. At another place area A₂= 5 cm². What is the pressure at […]
A layer of glycerine of thickness 1 mm present between a large surface area of 0.1 m². With what force the small surface is to be pulled, so that it can move with a velocity […]
A wire elongates by l mm when a load W is hanged from it. If the wire goes over a pulley and two weights W each are hung at the two ends, the elongation of […]
A bimetallic strip consists of metals X and Y. It is mounted rigidly at the base as shown. The metal X has a higher coefficient of expansion compared to that for metal Y. When the […]
A polished metal plate has a rough and black-spot. It is heated to 1400 K and brought immediately in dark room. Then
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(a) The spot will appear darker than the plate (b) The […]
A pan is suspended from a steel wire. Weights are slowly put on the pan and as the weight increases, the change in the length of the steel wire
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(a) Will be uniform […]
If a small sphere is let fall vertically in a large quantity of still liquid of density smaller than that of the material of the sphere
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(a) At first its velocity increases, but […]
The surface temperature of the sun which has maximum energy emission at 500 nm is 6000 K. The temperature of a star which has maximum energy emission at 400 nm will be
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(a) […]
A body is under stress F and has Young’s modulus Y, then the energy stored per unit volume equals to
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(a) F²/2Y (b) Y/2F² (c) 2Y/F² (d) 2F²/Y
Correct Answer:
F²/2Y
Explanation:
Energy […]
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