A record turntable is rotating at 33 rev/min. A watermelon seed is on the turntable 6.2 cm from the axis of rotation. (a) Calculate the acceleration of the seed, assuming that it does not slip. (b) What is the minimum value of the coefficient of static friction between the seed and the turntable if the seed is not to slip

To develop this problem we will apply the concepts related to the angular motion kinematic equations, as well as the concepts related to the balance of Forces (Friction and Newton's second law).

We will convert the angular velocity values into international units therefore

PART A)

Centripetal acceleration is defined as the product between the radius and the square of the angular velocity, then

PART B) The friction force must be equivalent to the centripetal force (in Terms of the Newton's second law) to maintain balance therefore,

Frictional Force:

Centripetal force

Equating the equations we will have,

Therefore the minimum value of the coefficient of static fricton will be 0.075

electrical potential energy =0.072 j

explanation:

electrical potential energy is given by

u= q δv

q= charge=6 c

δv= potential difference and is given by

δv= e d

e= electric field

d= distance=5 mm=0.005 m

δv=2.4 (0.005)=0.012 v

now electric potential energy= u= q δv

u=6 (0.012)

u=0.072 j