The hollow sphere, in which the circus motor cyelist performs his stunts ,has a diameter of 7m. Find the area available to the motor cyclist for riding.

The hollow sphere, in which the circus motor cyclist performs his stunts, has a diameter of 7m. Find the area available to the motor cyclist for riding.

Koushik got a playing top as his birthday present, which surprisingly had no colour on it. He wanted to colour it with his crayons. The top is shaped like a cone surmounted by a hemisphere. The entire top is 5 cm. in height and the diameter of the top is 3.5 cm. Find the area he has to colour. (Take pi=22/7 )

A cubical block of side 7 cm is surmounted by a hemi-sphere. What is the greatest diameter the hemi-sphere can have? Find the surface area of the solid.

In a refrigerator one removes heat from a lower temperature and deposits to the surroundings at a higher temperature. In this process, mechanical work has to be done, which is provided by an electric motor. If the motor is of 1kW power and heat is transferred from -3°C to 27°C, find the heat taken out of the refrigerator per second assuming its efficiency is 50% of a perfect engine.

A runner moves along the road at 2.0 ms^(1) in still air that is at a temperature of 29.0^(0) C. His surface area is 1.4 m^(2) , of which approximately 85% is exposed to the air. Find the rate of convective heat loss from his skin at a temperature 35.0^(0) C to the outside air? Coefficient of convection for dry air and bare skin at wind speed 2.0 ms^(-1) ' is 22 W/m2 ""^(@) C .

A car has two wipers which do not overlap. Each wiper has a blade of length 25 cm sweeping through an angle of 115^(@) . Find the total area cleaned at the sweep of the blades . (use pi=(22)/(7) )