Question

Please help. In an experiment, a metal sphere of mass 0.1kg is dropped from a height of 1.2m. The sphere makes a depression in the sand of 2cm. Gravitational field strength, g = 10N/kg.
Calculate the average retarding force acting on the sphere as it comes to rest in the sand.

Answer 1

retardation starts when it it hit the sand

now .. s=0.02m

v=0

now u = final speed of metal falling

v^2= 2x1.2 ×10

v^2= 240

v= 4root15

now v^2=u^2 +2as

0 = 240+2a0.02

240= -0.04a

- 600= m/s^2

force = -600 ×0.1
= -60N