Question 1

Which particle in the atom is responsible for carrying a negative electric charge?

Accepted Answer

Electron

Question 2

If an ebonite rod is rubbed with animal fur, as shown in the diagram, what happens to the charges on the rod and the fur?

Accepted Answer

The rod gains negative charge and the fur gains positive charge.

Question 3

Which law states that the net electric charge of an isolated system remains constant during any process?

Accepted Answer

Law of Conservation of Electric Charge

Question 4

A metal sphere is charged by contact with a negatively charged ebonite rod. What is the resulting charge on the sphere?

Accepted Answer

The sphere becomes negatively charged.

Question 5

Which material is classified as a semiconductor?

Accepted Answer

Silicon

Question 6

What is the SI unit of electric charge?

Accepted Answer

Coulomb

Question 7

How many electrons are there in one coulomb of negative charge? Use $$e = 1.60 	imes 10$$^{-19}$$ 	ext{ C}.$$

Accepted Answer

$$6.25 	imes 10$$^{18}$$

Question 8

Which of the following best describes the process of charging by induction?

Accepted Answer

Redistribution of charges within an object due to a nearby charged object, without direct contact.

Question 9

A gold-leaf electroscope is used to detect electric charge. What happens to the gold leaves when a net charge is present?

Accepted Answer

The leaves repel each other.

Question 10

Which equation represents Coulomb’s Law for the force between two point charges?

Accepted Answer

$$F = k \frac{q_1$ q_2$}{r^2$}$$

Question 11

In the Bohr model of the hydrogen atom, the electron orbits the proton at a radius of $$5.29 	imes 10$$^{-11}$$ m. If the charge of the electron is -1.60$$ 	imes $$10^{-19} C$$, what is the magnitude of the electrostatic force between the electron and proton?

Accepted Answer

$$8.22 	imes 10$$^{-8}$$ N

Question 12

If two point charges $$q_1 = 0.3$$ 	imes $$10^{-6} C $$and $$q_2 = 0.4$$ 	imes $$10^{-6} C $$are separated by $$0.2 m$$, what is the magnitude of the force between them? (Use $$k = 8.99 	imes 10^9$ N·m^2$/C^2$)

Accepted Answer

Question 13

Which of the following is true about conductors?

Accepted Answer

They allow electric charge to move freely through them.

Question 14

A plastic rod is brought near a metal sphere but does not touch it. The sphere is then connected to the ground. What is the resulting charge on the sphere after the ground connection is removed?

Accepted Answer

The sphere becomes positively charged.

Question 15

Which of the following statements about the force between two charges is correct?

Accepted Answer

The force is attractive if the charges are unlike and repulsive if the charges are like.

Question 16

A student uses a gold-leaf electroscope to test a charged object. If the leaves spread apart, what can be concluded?

Accepted Answer

The object is charged.

Question 17

Which equation is analogous to Coulomb’s Law in Newtonian gravity?

Accepted Answer

$$F = G \frac{m_1$ m_2$}{r^2$}$$

Question 18

If a negatively charged rod is brought near a plastic surface, what happens to the molecules on the surface?

Accepted Answer

They become polarized, with positive charges attracted to the rod.

Question 19

A student calculates the net force on a charge in a 2-dimensional arrangement using vector addition. Which formula should they use to find the magnitude of the net force?

Accepted Answer

$$F = \sqrt{F_x^2$ + F_y^2$}$$

Lec 1

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드