A factory makes spherical steel balls of radius 0.35 cm.
The machine can coat $1540 cm^{2}$ of surface in one run.
How many such balls can be coated in one run (take π = 22/7)?

Question

A factory makes spherical steel balls of radius 0.35 cm. The machine can coat 1540 cm^2 of surface in one run. How many such balls can be coated in one run (take π = 22/7)?

Accepted Answer

1000. One ball SA = 4*(22/7)*0.35*0.35 = 4*(22/7)*0.1225 = 1.54 cm^2. Number = 1540 / 1.54 = 1000 balls.

A factory makes spherical steel balls of radius 0.35 cm.
The machine can coat $1540 cm^{2}$ of surface in one run.
How many such balls can be coated in one run (take π = 22/7)?

Step-by-Step Solution

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More Class 9 Surface Area of a Sphere practice

A factory makes spherical steel balls of radius 0.35 cm.The machine can coat 1540cm2 of surface in one run.How many such balls can be coated in one run (take π = 22/7)?

Step-by-Step Solution

Master this chapter in 30 minutes a day.

More Class 9 Surface Area of a Sphere practice

A factory makes spherical steel balls of radius 0.35 cm.
The machine can coat $1540 cm^{2}$ of surface in one run.
How many such balls can be coated in one run (take π = 22/7)?