Physics-
General
Easy
Question
What should be the minimum force P to be applied to the string so that block of mass m just begins to move up the frictionless plane
- Mg tan
2
- Mg cot 2
- None
2
2
The correct answer is: Mg tan 2
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A thermally insulated vessel contains some water at 00C. The vessel is connected to a vacuum pump to pump out water vapour. This results in some water getting frozen. It is given Latent heat of vaporization of water at 0°C =21 × 105 J/kg and latent heat of freezing of water = 3.36 × 105 J/kg. The maximum percentage amount of water that will be solidified in this manner will be
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One end of a 2.35m long and 2.0cm radius aluminium rod (K = 235 W.m-1K-1) is held at 200C. The other end of the rod is in contact with a block of ice at its melting point. The rate in kg s-1 at which ice melts is
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