A golf ball has diameter equal to 4.1 cm. Its surface has 150 dimples each of radius 2mm. Calculate total surface which is exposed to the surroundings. (Assume that the dimples are all hemispherical) `" "[pi=22//7]`

Find the volume and the total surface area of a hemisphere of radius 7.5 cm. (pi=22/7)

Find the volume and the total surface area of a hemisphere of radius 3.5 cm. (pi=22/7)

Find the volume and surface area of a sphere of radius 2.1 cm. (pi=22/7)

The lower end of a capillary tube of diameter 2.00mm is dipped 8.00cm below the surface of water in a beaker. What is the pressure required in the tube in order to blow a hemispherical bubble at its end in water? The surface tension of water at temperature of the experiments is 7.30 times 10^2 Nm^-1 .1 atmospheric pressure =1.01 times 10^5 Pa density of water =1000 kg//m^3,g=9.80 ms^-2 . Also calculate the excess pressure.

A cylindrical pillar has a diameter of 56 cm and is of 35 m high. There are 16 pillars around the building. Find the cost of painting the curved surface area of all the pillars at the rate of ₹5.50 per 1 m^2