What can be said about the electric force between two charged particles?
a. it is repulsive for unlike charges.
b. it varies as 1/r.
c. it depends only on the magnitudes of the charges.
d. it is much, much greater than the attractive gravitational force.
The correct answer is a. It is repulsive for unlike charges.
To understand this, we need to recall Coulomb's Law. According to Coulomb's Law, the electric force between two charged particles is directly proportional to the product of their charges and inversely proportional to the square of the distance between them. Mathematically, it can be represented as:
F = k * (q1 * q2) / r^2
Where:
F is the electric force between the particles
k is the electrostatic constant (a constant value)
q1 and q2 are the magnitudes of the charges on the two particles
r is the distance between the particles
From this equation, we can make several observations:
a. The electric force is repulsive for unlike charges: If the charges on the particles have opposite signs (i.e., one is positive and the other is negative), their product will be negative. Since the force equation includes this product, the force between the particles will also be negative, which indicates a repulsive force.
b. The electric force varies as 1/r: As mentioned, the electric force is inversely proportional to the square of the distance between the charged particles. This means that as the distance between the particles increases, the force between them decreases. In other words, the force weakens rapidly as the distance increases.
c. The electric force depends only on the magnitudes of the charges: The force is directly proportional to the product of the magnitudes of the charges (q1 and q2). The sign (positive or negative) of the charges determines whether the force is attractive or repulsive, but the actual magnitude of the charges determines the strength of the force.
d. The electric force is much greater than the attractive gravitational force: Comparing the electric force to the gravitational force, we find that the electric force is typically much stronger. This is because the constant of proportionality for the electric force (k) is significantly larger than the gravitational constant (G), resulting in a greater force between charged particles compared to the force between masses due to gravity.