A golf ball has diameter equal to 4.1 centimetre its surface has 150 d...
Total surface area without dimples = 4 x 22/7 x 2.05^2 = 52.83 cm2
Total area where the dimples are = 22/7 x 0.22 x 150 = 18.857 cm2
Area where there are no dimples = 52.83 - 18.857 = 33.973 cm2
Area of the dimples = 1/2 x 4 x 22/7 x 0.22 x 150 = 37.714 cm2
Surface area exposed to surroundings = Area with no dimples + area of dimples
= 33.973 + 37.714 = 71.687 cm2
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A golf ball has diameter equal to 4.1 centimetre its surface has 150 d...
Diameter of the golf ball:
Given that the diameter of the golf ball is 4.1 centimeters.
Radius of the golf ball:
The radius of the golf ball can be calculated by dividing the diameter by 2. So, the radius is 4.1 cm / 2 = 2.05 cm.
Number of dimples:
It is mentioned that the golf ball has 150 dimples.
Radius of each dimple:
The radius of each dimple is given as 2 mm.
Conversion of radius to centimeters:
To calculate the total surface area, we need to convert the radius of each dimple from millimeters to centimeters. Since 1 cm = 10 mm, the radius of each dimple is 2 mm / 10 = 0.2 cm.
Surface area of each dimple:
The surface area of each dimple can be calculated using the formula for the area of a circle, which is π * r^2. Therefore, the surface area of each dimple is π * (0.2 cm)^2.
Total surface area:
To find the total surface area, we need to multiply the surface area of each dimple by the number of dimples and add it to the surface area of the golf ball without the dimples.
The surface area of the golf ball without the dimples can be calculated using the formula for the surface area of a sphere, which is 4 * π * r^2, where r is the radius of the golf ball.
Therefore, the total surface area of the golf ball is:
Total surface area = surface area of golf ball without dimples + (surface area of each dimple * number of dimples)
Calculating the surface area:
1. Calculate the surface area of the golf ball without dimples:
Surface area of golf ball without dimples = 4 * π * (2.05 cm)^2
2. Calculate the surface area of each dimple:
Surface area of each dimple = π * (0.2 cm)^2
3. Calculate the total surface area:
Total surface area = surface area of golf ball without dimples + (surface area of each dimple * number of dimples)
Final answer:
Perform the calculations using the appropriate values and units to find the total surface area of the golf ball.
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