Electric Charge
What are the two types of electric charge?
Positive and negative.
Coulomb’s constant k = ?
8.99 × 10⁹ N·m²/C²
If a charge experiences 6 N right and 2 N left, net force = ?
4 N right.
Charge of a proton?
+1.602 × 10⁻¹⁹ C.
Electrostatic force formula?
F=kq1q2/r2
Does superposition apply even if forces are attractive and repulsive at the same time?
Yes.
Charge of an electron?
–1.602 × 10⁻¹⁹ C.
q1=+2μC and q2=+3 μC
are 0.5 m apart.
Find the force between them.
Final Answer: 0.216 N (repulsive)
In 1D superposition problems, rightward forces are usually considered…
Positive.
Object becomes positively charged when it…
Loses electrons.
q1=+5μC and q2=−2 μC r=0.3 m , F=?
Final Answer: 1 N (attractive)
If three forces act on a charge: 3 N right, 5 N left, 1 N right → net force = ?
1 N left.
Which materials resist the flow of charges?
Insulators.
Three charges are placed on a straight line:
q1=+4 μCq_1 = +4, x = 0 m
q2=+4 μCq_2 = +4, x = 1 m
q3=+4 μCq_3 = +4, x = 3 m
Find the net force on q2
F21=0.144N (right)