A steel ball is used to measure the viscosity of motor oil. The container used in this experiment has a bottom area of 20 cm^2. The steel ball is 3 mm in diameter. After the ball is dropped to the container it takes about 12 seconds to reach the bottom of the container whose height is 60 cm. Calculate the viscosity of the motor oil.

Answer 1

dragforce=6π*radius*vicosity*speed.
so if the ball is falling at a constant rate, the dragforce=forcegravity=m*9.8
so viscosity= 9.8/(6PI*0.0015*.6/12