a golf ball has diameter equal to 4.1cm. Its surface has 150 dimples each of radius 2mm. Calculate total surface area exposed to the surrondings assuming that the dimples are hemispherical.
I WANT THE ANSWER WITH FUUL EXPLANATION AT EACH STEP. THE LINK WSA NOT ABLE TO SATISFY ME
Given, diameter of golf ball = 4.1 cm
⇒ radius of golf ball
Now, surface area of golf ball without dimples
It is given that the shape of dimples is hemispherical and radius of each dimple = 2 mm = 0.2 cm
∴ area of each dimple =
So, area of 150 dimples = 150 × area of each dimple = 150 × 0.08π = 12π cm2
Area of flat surface removed to make 1 dimple
∴ area of flat surface removed to make 150 dimples
Now, total surface area of golf ball exposed to surroundings = surface area of golf ball without dimples + area of 150 dimples - area of flat surface removed to make 150 dimples
= 16.81π + 12π - 6π = 22.81π cm2