Q: What is the magnitude of the charge of a single electron?

$$e = 1.602 \times 10$$^{-19}$$ \ \mathrm{C}$$

Q: If two ping-pong balls, each of mass $$0.010 \ \mathrm{kg}$$, are separated by $$0.01 \ \mathrm{m}$$ and have charges $$+1.0 \times 10$$^{-9}$$ \ \mathrm{C}$$ and $$-3.0 \times 10$$^{-10}$$ \ \mathrm{C}$$, what is the magnitude of the electric force between them?

$$2.7 \times 10$$^{-5}$$ \ \mathrm{N}$$

Q: If the only force acting on a proton is the electric force from another proton ($$F = 25.6 \ \mathrm{N}$$), and the mass of a proton is $$1.67 \times 10$$^{-27}$$ \ \mathrm{kg}$$, what is the acceleration experienced by the proton?

$$a = 1.54 \times 10$$^{28}$$ \ \mathrm{m/s^2$}$$

Q: A negatively charged oil drop is held motionless in a uniform electric field of magnitude $$5.0 \times 10^5$ \ \mathrm{N/C}. If $$the mass of the drop is $$2.45 \times 10$$^{-15}$$ \ \mathrm{kg}$$, what is the charge on the drop?

$$q = -4.8 \times 10$$^{-19}$$ \ \mathrm{C}$$

Question 1

Which subatomic particle is responsible for the negative charge in an atom?

Accepted Answer

Electron

Question 2

What is the magnitude of the charge of a single electron?

Accepted Answer

$$e = 1.602 	imes 10$$^{-19}$$ \ \mathrm{C}$$

Question 3

According to Coulomb’s law, what happens when two like charges are brought close together?

Accepted Answer

They repel each other

Question 4

Given two charges $$q_1$$ and $$q_2$$ separated by a distance $$r$$, what is the formula for the magnitude of the electric force between them?

Accepted Answer

$$|\vec{F}| = \dfrac{k|q_1$||q_2$|}{r^2$}$$

Question 5

If two ping-pong balls, each of mass $$0.010 \ \mathrm{kg}$$, are separated by $$0.01 \ \mathrm{m}$$ and have charges $$+1.0 	imes 10$$^{-9}$$ \ \mathrm{C}$$ and $$-3.0 	imes 10$$^{-10}$$ \ \mathrm{C}$$, what is the magnitude of the electric force between them?

Accepted Answer

$$2.7 	imes 10$$^{-5}$$ \ \mathrm{N}$$

Question 6

A proton and another proton inside a helium nucleus are separated by $$3.00 	imes 10$$^{-15}$$ \ \mathrm{m}. $$What is the magnitude of the electric force between them?

Accepted Answer

$$25.6 \ \mathrm{N}$$

Question 7

If the only force acting on a proton is the electric force from another proton ($$F = 25.6 \ \mathrm{N}$$), and the mass of a proton is $$1.67 	imes 10$$^{-27}$$ \ \mathrm{kg}$$, what is the acceleration experienced by the proton?

Accepted Answer

$$a = 1.54 	imes 10$$^{28}$$ \ \mathrm{m/s^2$}$$

Question 8

Why does a child’s hair stand up at the bottom of a plastic playground slide?

Accepted Answer

Charge builds up on the child through transfer of electrons during the slide

Question 9

If Sphere 2 has three times the charge of Sphere 1 and both are positively charged, what is true about the electric forces they exert on each other?

Accepted Answer

The forces are equal in magnitude and opposite in direction

Question 10

Which of the following best describes the SI unit of electric charge?

Accepted Answer

Coulomb (C)

Question 11

If the distance between two point charges is doubled, what happens to the magnitude of the electric force between them according to Coulomb’s law?

Accepted Answer

It decreases by a factor of 4

Question 12

A negatively charged oil drop is held motionless in a uniform electric field of magnitude $$5.0 	imes 10^5$ \ \mathrm{N/C}. If $$the mass of the drop is $$2.45 	imes 10$$^{-15}$$ \ \mathrm{kg}$$, what is the charge on the drop?

Accepted Answer

$$q = -4.8 	imes 10$$^{-19}$$ \ \mathrm{C}$$

Question 13

Which of the following statements about electric charge is correct?

Accepted Answer

Protons have a positive charge, electrons have a negative charge, and neutrons are neutral

Question 14

If the electric force between two charges is $$F$$, and the magnitude of one charge is doubled, what happens to the force?

Accepted Answer

The force doubles

Question 15

A student rubs a balloon on their hair and the balloon sticks to the wall. Which process is responsible for the balloon acquiring charge?

Accepted Answer

Transfer of electrons between the balloon and hair

Question 16

Which of the following is NOT a property of electric charge?

Accepted Answer

Electric charge can be created or destroyed

Question 17

If the force between two charges is $$2.7 	imes 10$$^{-5}$$ \ \mathrm{N}$$ and each mass is $$0.010 \ \mathrm{kg}$$, what is the acceleration of each mass?

Accepted Answer

$$2.7 	imes 10$$^{-3}$$ \ \mathrm{m/s^2$}$$

Question 18

Which of the following best explains why the electric force between two protons in a nucleus is repulsive?

Accepted Answer

Both protons have positive charge

Question 19

Which of the following is the correct value for the Coulomb constant $$k$$ used in Coulomb’s law?

Accepted Answer

$$9.0 	imes 10$$^{9}$$ \ \mathrm{N \cdot m^2$ / C^2$}$$

week 7

Study Guide - Practice Questions

Study Guide - Flashcards