PHYSICS 12 ELECTROSTATICS WORKSHEET 1
1. How much force is exerted between two charged objects that are separated by a distance
of 1.5 m if both objects have a charge of +3.0 C?
2. Deuterium atoms contain one proton and one neutron in the nucleus with one electron
orbiting at a distance of 5.10 x 10-11 m.
a) Calculate the magnitude of the gravitational force of attraction between the nucleus and
the electron.
b) Calculate the magnitude of the electrical force of attraction between the nucleus and
the electron.
3. A metal sphere has a net charge of -4 C. How many excess electrons does the metal
sphere contain?
4. What is the total charge of 1 gram of electrons?
5. An alpha particle (2 protons, 2 neutrons) is placed between two stationary, charged
objects as shown. It is 0.0030 m to the right of the object carrying a +1.0 x 10-12 C charge
and 0.0020 m to the left of the object carrying a -2.0 x 10-12 C charge, as shown below.
α
0.0030 m 0.0020 m
-12
+1.0 x 10 C -2.0 x 10-12 C
a) What is the net magnitude and direction of the electrical force acting on the α particle?
b) At what rate and in what direction will the α particle accelerate?
6. The force of attraction between two equal but opposite 3.0µC charges is 4.0 x 10-3 N.
What distance separates the charges?
7. In each of the following diagrams, solve for the new force FAB:
a) 1.0 cm 1.5 cm
+q -q +q -q
FAB= 3.0 x 10-6 N FAB= ?
b) 1.0 cm 1.0 cm
+q -q +q/2 -3q/2
-4
FAB= 8.0 x 10 N FAB= ?
c) 1.73 m 0.5 m
+q +2q +q/4 +6q
-6
FAB= 1.0 x 10 N FAB= ?
d) 3.0 cm 2.3 cm
+q +q +q +q/2
FAB= 2.4 x 10-3 N FAB= ?
8. Three charged particles are 5.00 µC 7.00 µC
positioned as shown to the 3.00 cm
right.
2.00 cm
Determine the magnitude of
the net force acting on:
a) the 5.00 µC charge; 4.20 µC
b) the 7.00 µC charge.
9. A If all charges A, B and C are identical, and
if the force acting on charges B-C is
FBC = 1.2 x 10-3 N, then determine the
1.7 cm net force on charge B, including direction.
3.0 cm
B C
10. Examine the position of the charges
to the right. If the triangle shown C +3q
is equilateral, and the force acting
on charges A-B is FAB = 3.0 x 10-3 N,
then determine the magnitude and
direction of :
a) the net force on C; A B
b) the net force on B.
+q -q
10 -47 -8 19 8 -15
1. 3.6 x 10 N 2. a) 7.8 x 10 N b) 8.8 x 10 N 3. 2.5 x 10 4. -1.76 x 10 C 5. a) 1.76 x 10 N right b)
11 2 -6 -4 -6 -3
2.63 x 10 m/s right 6. 4.5 m 7. a) 1.3 x 10 N b) 6.0 x 10 N c) 9.0 x 10 N d) 2.0 x 10 N
-3 -3
8. a) 588 N b) 532 N 9. 3.8 x 10 N @ 72° down to left 10. a) 9.0 x 10 N horizontal to right
-2
b) 1.1 x 10 N @ 46° up to left
