1. How is the attractive electrostatic force between a proton and an electron indicated in Coulomb's law?
A. The sum of the charges indicates a positive force
B. The sum of the charges indicates a negative force
C. The product of the charges indicates a positive force *****
D. The product of the charges indicated a negative force
2. One particle has a negative charge, while another particle is neutral. Which statement describes the electrostatic force between these two particles?
A. The electrostatic force is repulsive due to the particle with negative charge.
B. There would be no electrostatic force because the sum of the two charges is 0.
C. The electrostatic force is attractive due to the particle with negative charge. ****
D. There would be no electrostatic force because the product of the two charges is 0.
3. How would the electrostatic force change if Coulomb's law included a negative sign?
A. Like charges would repel, and opposite charges would attract.
B. Like charges would attract, and opposite charges would repel. ***
C. It would not make a difference in the electrostatic force.
D. It would depend on the magnitude of the charges.
4. What is the value and the direction of an electric field at a distance of 2.5 m from a +1 nC charge?
A. approximately 1.45 V/m directed away from the positive charge
B. approximately 145 V/m directed toward the positive charge
C. approximately 145 V/m directed away from the positive charge
D. approximately 1.45 V/m directed toward the positive charge ***
To answer these questions, we need to refer to Coulomb's law, which relates the electrostatic force between two charged particles to their charges and the distance between them. The formula is:
F = k * (q1 * q2) / r^2
Where:
- F is the electrostatic force between the particles,
- k is the electrostatic constant (approximately equal to 8.99 * 10^9 Nm^2/C^2),
- q1 and q2 are the charges of the particles, and
- r is the distance between the particles.
Now, let's address each question:
1. How is the attractive electrostatic force between a proton and an electron indicated in Coulomb's law?
The attractive electrostatic force between a proton and an electron is indicated in Coulomb's law through the product of the charges (q1 * q2). Since a proton has a positive charge and an electron has a negative charge, their product would be negative. Therefore, option D is incorrect.
2. One particle has a negative charge, while another particle is neutral. Which statement describes the electrostatic force between these two particles?
In this case, we have a negative charge on one particle and a neutral charge (which is effectively zero) on the other. Thus, the product of the charges (q1 * q2) would be negative, indicating an attractive force. Therefore, option C is correct.
3. How would the electrostatic force change if Coulomb's law included a negative sign?
If Coulomb's law included a negative sign, it would reverse the direction of the force. This means that like charges would attract, and opposite charges would repel. Therefore, option B is correct.
4. What is the value and the direction of an electric field at a distance of 2.5 m from a +1 nC charge?
To find the electric field at a distance from a charge, we can use the formula:
E = k * (q / r^2)
Where:
- E is the electric field,
- k is the electrostatic constant,
- q is the charge, and
- r is the distance from the charge.
Plugging in the values, we get:
E = (8.99 * 10^9 Nm^2/C^2) * (+1 nC) / (2.5 m)^2
Evaluating this expression, we find that the electric field at a distance of 2.5 m from a +1 nC charge is approximately 1.45 V/m. Additionally, since we have a positive charge, the direction of the electric field would be directed away from the positive charge. Therefore, option D is correct.