A physics student took a solid sphere of density 2 g `cm^(-3)` and radius 3.5 cm and applied a force on the sphere. If an acceleration fo 1.5 `cm s^(-2)` is produced in it, find the amount of force applied on it.

Explanation

Given, acceleration, a = 1.5 cm `s(-2)`
Radius of sphere, r = 3.5 cm
Density of sphere = 2 g `cm^(-3)`
Force, F = (mass) (acceleration)
But mass, M = (volume) (density),
Volume `V = (4)/(3) pi r^(3) = (4)/(3) xx (22)/(7) xx (3.5)^(3) cm^(3)`
`thereforeM = (4)/(3)xx (22)/(7)xx ((7)/(2))^(3) xx 2=(1078)/(3)g`
`therefore " Force, "F = (1078)/(3) xx 1.5 " dyne "=(1078)/(2) = 539` dyne.