Answer:
894 electrons
Explanation:
The electrostatic force between the two charges is given by:
where we have
is the force
k is the Coulomb's constant
q1 = q2 =q is the magnitude of the charge on each sphere
r = 20.0 cm = 0.20 m is the distance between the two spheres
Substituting and solving for q, we find the charge on each sphere:
And since each electron has a charge of
the net charge on each sphere will be given by
where N is the number of excess electrons; solving for N,
1) Displacement: -49 m, in the negative direction
Explanation:
The displacement of an object is a vector, whose magnitude is given by the difference between the final point of the motion and the starting point:
In this problem, the starting point is +34 m, while the final position is -15 m; therefore, the displacement is:
and the direction is negative, in according to the negative sign.
2) Velocity: -3.27 m/s
Explanation:
Velocity is equal to the ratio between the displacement and the time taken:
in this problem, we have:
d = -49 m is the displacement
t = 15 s is the time
therefore, the velocity is
and the direction is negative.