A 4 m long aluminium wire whose diameter is 3 mm is used to support a mass of 50 kg. What will be the elongation of the wire ? Y for aluminium is `7 xx 10^(10) N//m^2`.

An aluminium sphere of diameter 20 cm is heated from 0^(@)C " to " 100^(@)C . What will be its change in volume? Coefficient of linear expansion of aluminium =23 times 10^(-6@)C^(-1) .

One end of an aluminium wire whose diameter is 2.5 mm is welded to one end of a copper wire whose diameter is 2.0 mm. The composite wire carries a steady current of 6.25A. What is the current density in each wire ?

A body of mass 4 kg and density 2.5 g.cm^-3 , suspended by a metallic wire of length 1 m and diameter 2mm, is kept completely immersed in water. What will be the increase in the length of the wire? Young's modulus of the metal =2 times 10^11 N.m^-2 and g=9.8 m.s^-2 .

Two equal and opposite forces are applied tangentially to two mutually opposite faces of an aluminium cube of side 3 cm to produce a shear of 0.01^@ . IF the modulus of rigidity for aluminium is 7 times 10^10 N.m^-2 , then calculate the force applied.

A rubber cord of length 20 m is supplied from a rigid support by one of its ends it hangs vertically. What will be the elongation of the cord due to its own weight? The density of rubber= 1.5 g.cm^-3 and Young 's modulus= 49 times 10^7 N.m^-2 .

A body of mass 2kg and density 2.7 g. cm^-3 is suspended by a steel wire of length 1 m and radius 1 mm. IF the body is completely immersed In water, what will be the change in length of the wire? Y of steel =2 times 10^2 dyn.cm^-2 and g=980 cm.s^-2

A 10m long horizontal wire, lying along the magnetic east-west direction, begins to fall with a velocity of 5.0 m. s^(-1) . What will be the emf induced in the wire? [Given, H=0.3xx10^(-4)Wb.m^(-2) ]

A wire of length L and cross section A hung from a rigid support is loaded with a mass M The elongation produced is