A steel wire elongates by $\mathrm{\ell }\backslash ell$ mm, when a 5 kg load in hanged from it. The wire is now passed over a pulley and two loads of 4 kg and 2 kg are hung at the two ends. The elongation in the wire will be

The change in volume caused on stretching a rubber chord along its length is negligible. The Poisson's ratio for the material of the chord is

A closed enclosure contains an ideal gas. The pressure exerted by gas is same at all points inside enclosure. The enclosure is given an acceleration (uniform) in horizontal direction. The pressure in compartment now is

A bubble of a liquid of surface tension S is blown to a radius r. The work done in blowing bubble is W. The percentage change in work done in doubling the radius of the bubble is

The cylindrical tub of a spray gun has an area of cross-section A. The other end has N holes each of cross-sectional area a. The speed of liquid of the broader end is v. The speed of ejection of liquid from each hole of spray gun is

A spherical bubble is trapped inside a liquid of density ${\rho }_1\backslash rho\_1$; coefficient of viscosity $\eta \backslash eta$. The bubble starts rising upwards. Besides the buoyant force; the following forces act on it.

Water emerges out of a garden hose pipe. Assuming flow is streamlined which of the following statement is correct?

A small sphere of radius r falls from rest in a viscous medium of coefficient of viscosity η. Heat is produced in sphere due to the viscous force of medium. The rate of heat produced in sphere when it has acquired terminal velocity is proportional to

A geyser heats water flowing in it at the rate of 50 cc $s^{-1}s^\{-1\}$ from $27^{\circ }C27^\backslash circ\; C$ to $77^{\circ }C77^\backslash circ\; C$. The geyser operates on a gas burner. It consumes 0.6 kg of gas per hour. The heat of combustion of gas is

Two spheres A and B of same material have radii R and 4R. The temperature of A and B are 4T and 2T on absolute scale. The ratio of the energy radiated per second by the A and B is