The resistance of a resistor is reduced to half of its initial value. In doing so, if other parameters of the circuit remain unchanged, the heating effects in the resistor will become
(A) two times
(B) half
(C) one - fourth
(D) four times

If earth radius reduces to half of its present value then the time period of rotation will become:

If diameter of earth becomes half of its present value and its mass becomes four times its present value, how would the weight of any object on the surface of earth be affected ?

The radius of a wire is decreased to one-third. If volume remains the same, the length will become 3 times (b) 6 times (c) 9 times (d) 27 times

If the side of a square are halved, then its area (a) remains same (b) becomes half (c) becomes one fourth (d) becomes double

A certain radioactive material is known to decay at a rate proportional to the amount present. If initially there is 50 kg of the material present and after two hours it is observed that the material has lost 10% of its original mass, find () and expression for the mass of the material remaining at any time t, (ii) the mass of the material after four hours and (iii) the time at which the material has decayed to one half of its initial mass.

A certain radioactive material is known to decay at a rate proportional to the amount present. If initially there is 50 kg of the material present and after two hours it is observed that the material has lost 10% of its original mass, find () and expression for the mass of the material remaining at any time t, (ii) the mass of the material after four hours and (iii) the time at which the material has decayed to one half of its initial mass.

A resistance of 20 Omega is connected to a source of alternating current rated 110 V, 50 Hz . Find (a) the rms current, (b) the maximum instantaneous current in the resistor and (c) the time taken by the current to change from its maximum value to the rms value.

When volume of system is increased two times and temperature is decreased half of its initial temperature, then pressure becomes ………….

If the diameter of the earth becomes two times its present value and its mass remains unchanged then how would the weight of an object on the surface of the earth be affected ?

In the figure, the value of resistors to be connected between C and D so that the resistance of the entire circuit between A and B does not change with the number of elementary set used is