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

You may have seen in a circus a motorcyclist driving in vertical loops inside a 'death- well' ( a hollow spherical chamber with holes, so the spectators can watch from outside). Explain clearly why the motorcyclist does not drop down when he is at the uppermost point, with no support from below. What is the minimum speed required at the uppermost position to perform a vertical loop if the radius of the chamber is 25 m?

Find the surface area of a sphere of diameter: 3.5m

A cylinderical pipe has an outer diameter of 1.4 m and an inner diameter of 1.12m. Its length is 10 m. Find the total area to be painted if the rate of painting is Rs. 100 per m^2 .

A circular cycle track has a circumference of 314 m with AB as one of its diameter.s A cyclist travels form A to B along the circular path with a velocity of constant magnitude 15.7 m/s. Find the displacement of the cyclist of AB represents north -south direction, with A towards North and B towards south.