The opposite faces of a cubical block of iron and cross-section 4 sq. cm are kept in contact with steam of melting ice. Calculate the amount of ice melted at the end of 10 minutes if `K = 0.2 cal cm^-1s^-1C^-1` for iron.

A thermocole box is a cheap and effieicnet method for storing small quantity of cooked food in summer in particular. A cubical box of side 30 cm has a thickness of 5 cm. If 4 kg of ice are put in a box. Estimate the amount of ice remaining after 6 h. The outside temperature 45^@C , and coefficient K = 0.01 J s^-1 m^-1 k^-1 [Heat of fusion of water = 335 xx 10^3 J kg^-1] .

Find the amount of heat required to convert 1g ice at 0^@ C into steam at 100^@ C .

A copper wire of resistivity 1.6xx10^-8 ohm-m has a cross sectional area of 20xx10^-4 cm^2 . Calculate the length of wire required to make a 10 ohm coil.

An iron rod of 0.1 m^2 area of cross-section subjected to a magnetising field of 1,000 Am^-1 . Calculate its magnetic permeability. Given susceptibility of iron is 59.9.

A long solenoid of 10 turns / cm has a small loop of area 1 sq. cm placed inside with the normal of the loop parallel to the axis. Calculate the placed across the small loop if the current in the solenoid is changed from 1 A to 2 A in 0 .1 s, during the duration of this change.

The resistance of a 0.25 mol or solution of an molar solution of an electrolyte was found to be 75Omega . Calculate the molar conductivity of the solution if the electrods in the cell are 1.8 cm a part and having an area of cross section 3.6cm^(2) .

A current of 1 A flows through a wire of length 0.24m and area of cross-section 1.2mm^2 , when it is conneted to a battery of 3V. Find the number density of free electrons in the wire, if the electron mobility is 4.8 xx 10^-6 m^2 V^-1s^-1 , given that charge on electron = 1.6 xx 10^-19C

A metal rod of length 10 cm and a rectangular cross-section of 1 cm xx 1/2 cm is connected to a battery across opposite faces. The resistance will be:

A coper block of mass 2.5 kg is heated in a furnace to a temperature of 500 ^@C and then placed on a large ice block. What is the maximum amount of ice that can melt? (specific heat of copper = 0.39 J g^-1 C^-1 , heat of fusion of watter = 335 J g^-1 ).

A cone is 8.4 cm high and the radius of its base is 2.1 cm. It is melted and recast into a sphere. The radius of the sphere is