A piece of radioactive material contains 1000 atoms. If its half-life is 20 seconds, the time taken for 125 atoms to remain is Posted on:
If a pump is capable of lifting 5000 kg of water through a vertical height of 60 m in 15 min, the power of the pump is Posted on:
An object is moving with a velocity of 5ms-1. At what height must a similar body be situated to have a potential energy equal in value with the kinetic energy of the moving body? Posted on:
A house is supplied with a 240V a.c mains. To operate a door bell rated at 8V, a transformer is used if the number of turns in the primary coil of the transformer is 900. Calculate the number of turns in the secondary coil of the transformer Posted on:
In the circuit above R is a resistor whose resistance increases with increases with increase in temperature L1 and L2 are identical lamps. If the temperature of R increases Posted on:
A piece of cork floats in a liquid. What fraction its volume will be immersed in the liquid? [density of the cork = 0.25 × 103kgm-3, Density of the liquid = 1.25 × 103kgm-3] Posted on:
A train with an initial velocity of 20ms-1 is subjected to a uniform deceleration of 2ms-2. The time required to bring the train to a complete halt is Posted on:
Calculate the apparent weight loss of a man weighing 70kg in an elevator moving downwards with an acceleration of 1.5ms-2. Posted on:
A 90W immersion heater is used to supply energy for 5 minutes. The energy supplied is used to completely melt 160g of a solid at its melting point. Calculate the specific latent heat of the solid. Posted on: