Answer:

Explanation:
Let the charge on the ball bearing is q.
charge on glass bead, Q = 20 nC = 20 x 10^-9 C
Force between them, F = 0.018 N
Distance between them, d = 1 cm = 0.01 m
By use of Coulomb's law in electrostatics

By substituting the values


Thus, the charge on the ball bearing is 
Answer:
v = 10 m/s
Explanation:
given,
Mass of Mercedes engine = 2000 Kg
Power delivered = 100 kW
angle made with horizontal = 30°
acceleration due to gravity = 10 m/s²
largest speed car can sustain = ?
we know,
Power = Force x velocity
P = F x v
P = mg sinθ x v
P = mg sin 30° x v
P = 0.5 mg x v

v = 10 m/s
hence, the maximum velocity is equal to v = 10 m/s
I think A but I dont really know