Physics Test 13...

In the figure shown the acceleration of A is, , then the acceleration of B is : (A remains in contact with B)

The speed of sound in hydrogen gas at N.T.P. is 1,328 ms^-1. What will be its value in air at N.T.P., if density of hydrogen is 1/16th that of air?

A balloon that is initially flat, is inflated by filling it from a tank of compressed air. The final volume of the balloon is 5m³. The barometer reads 95 kPa. The work done in this process is

Two bodies of same mass tied with an inelastic string of length   together on a horizontal surface. One a horizontal surface of them is projected vertically upwards with velocity  ⁡Find the maximum height up to which the centre of mass of system of the two masses rises.

The electric potential at a point (x, y, z) is given by V = -x²y - xz³ + 4 The electric field  at that point is

Binding energy per nucleon versus mass number curve for nuclei is shown in figure. W, X, Y and Z are four nuclei indicated on the curve. The process that would release energy is

A wire of length 1.0 m and radius 10^-3 m is carrying a heavy current and is assumed to radiate as a black body. At equilibrium, its temperature is 900 K while that of the surroundings is 300 K. The resistivity of the material of the wire at 300 K is π² × 10^-8 ohm-m and its temperature coefficient of resistance is 7.8× 10⁻³ C^o. Find the current in the wire. [Given Stefan's constant = 5.68 × 10^-8 W/m²K⁴]

50 V battery is supplying a steady current of 10 amp when connected to an external resistor. If the efficiency of the battery at this current is 25%, then internal resistance of battery is:

A capacitor of capacitance C is charged to a potential difference V from a cell and then disconnected from it. A charge +Q is now given to its positive plate. Now, the potential difference across the capacitor is.

Energy from the sun falls on the earth at a rate of 1353 W/m², which is known as solar constant, i.e., the power incident per unit area per second at the top of atmosphere. Find the r.m.s values of the electric and magnetic fields in the sunlight reaching the top of the atmosphere.