Answer:
(A) 7.9 m/s^{2}
(B) 19 m/s
(C) 91 m
Explanation:
initial velocity (U) = 0 mph = 0 m/s
final velocity (V) = 85 mph = 85 x 0.447 = 38 m/s
initial time (ti) = 0 s
final time (t) = 4.8 s
(A) acceleration = 
=
= 7.9 m/s^{2}
(B) average velocity = 
=
= 19 m/s
(C) distance travelled (S) = ut + 
= (0 x 4.8) +
= 91 m
Answer:
F = 5.33*10^-4N
Explanation:
to find the electrostatic force you use the Coulomb's law, given by the formula:

k: Coulomb's constant = 8.89*10^9 Nm^2/C^2
q_a: charge of A = 2.0*10^{-6}C
q_B: charge of B = -3.0*10^{-6}C
r: distance between the spheres = 10.0m
By replacing all these values you obtain:

hence, the forcebetween the spheres is about 5.33*10^-4N