PHYSICS CHAPTER 22

How does a semiconductor differ from a conductor or an insulator? A. A semiconductor is neither a good conductor nor a good insulator - it has a middle range of resistivity. B. A semiconductor is a good conductor of electric current but a poor conductor of heat. C. A semiconductor has exactly half the resistance of an insulator and twice the resistance of a conductor. D. A semiconductor has exactly half the resistance of a conductor and twice the resistance of an insulator.

A. A semiconductor is neither a good conductor nor a good insulator - it has a middle range of resistivity.

What kind of charging occurs when you slide your body across a plastic surface? A. Charging by friction occurs. Electrons are transferred when one object rubs against another. B. Charging by induction occurs. Electrons in one object push away electrons in the other object. C. Charging by friction occurs. Electrons move from a neutral object to a negatively charged object. D. Charging by touching occurs. Electrons move from a negatively charged object to a neutral object.

A. Charging by friction occurs. Electrons are transferred when one object rubs against another

What is the most common net charge of an atom? A. Neutral B. Negative C. Positive D. Dipole

A. Neutral

The electrical force between charges is strongest when the charges are A. close together. B. far apart. C. either of these D. need more information

A. close together.

An electrically charged atom is an A. ion. B. isotope. C. both of these D. neither of these

A. ion.

If you comb your hair and the comb becomes positively charged, then your hair becomes A. negatively charged. B. positively charged. C. uncharged.

A. negatively charged.

Which of these does NOT have an electrical charge? A. neutron B. electron C. proton D. all of the above E. none of the above

A. neutron

Which of these has the greatest mass? A. proton B. electron C. both of these D. neither of these

A. proton

Electric potential, unlike electric potential energy, is measured in units of _________. A. volts B. conduction C. coulombs D. joules

A. volts

Given that k=9.0×109N⋅m2/C2 (the proportionality constant for Coulomb's law), select the correct equations that show that the force between the charges is 4×109N. A. F=kq1q2r=(9.0×109N⋅m2/C2)⋅(0.2C)⋅(0.2C)0.3m=4×109N B. F=kq1q2r2=(9.0×109N⋅m2/C2)⋅(0.2C)⋅(0.2C)(0.3m)2=4×109N C. F=krq1=(9.0×109N⋅m2/C2)⋅(0.3m)0.2C=4×109N D. F=kr2q1q2=(9.0×109N⋅m2/C2)⋅(0.3m)2(0.2C)⋅(0.2C)=4×109N

B. F=kq1q2r2=(9.0×109N⋅m2/C2)⋅(0.2C)⋅(0.2C)(0.3m)2=4×109N

What is an electric dipole? A. An electric dipole is made up of two positive charges separated by a small distance. B. In an electric dipole, positive and negative charges are separated on opposite sides of an object. C. In an electric dipole, positive charges are inside a molecule while negative charges are outside. D. An electric dipole is made up of two negative charges separated by a small distance.

B. In an electric dipole, positive and negative charges are separated on opposite sides of an object.

Which part of an atom is positively charged, and which part is negatively charged? A. Atoms are made entirely of neutral particles. B. The nucleus is positively charged and the electron cloud is negatively charged. C.The core is positively charged, the mesosphere is neutrally charged, and the exosphere is negatively charged. D. The nucleus is negatively charged and the electron cloud is positively charged.

B. The nucleus is positively charged and the electron cloud is negatively charged.

An electron and a proton A. repel each other. B. attract each other. C. neither attract nor repel each other.

B. attract each other.

The force that binds atoms together to form molecules is A. nuclear. B. electrical. C. gravitational. D. centripetal. E. none of the above

B. electrical.

In an electrically neutral atom the number of protons in the nucleus is equal to the number of A. both electrons and neutrons. B. electrons that surround the nucleus. C. neutrons in the nucleus. D. none of the above

B. electrons that surround the nucleus.

To become a positive ion, an atom must A. gain an electron. B. lose an electron. C. gain a proton. D. lose a proton.

B. lose an electron.

What is a positive ion? What is a negative ion? A. A positive ion is a neutral atom that has lost one or more protons. A negative ion is a neutral atom that has gained one or more protons. B. A positive ion is a neutral atom that has gained one or more electrons. A negative ion is a neutral atom that has lost one or more electrons. C. A positive ion is a neutral atom that has lost one or more electrons. A negative ion is a neutral atom that has gained one or more electrons. D. A positive ion is a neutral atom that has lost one or more neutrons. A negative ion is a neutral atom that has gained one or more neutrons.

C. A positive ion is a neutral atom that has lost one or more electrons. A negative ion is a neutral atom that has gained one or more electrons.

Why are materials such as glass and rubber good insulators? A. Electrons are tightly bound to their atoms, making them good conductors of heat. B. Electrons are loosely bound to their atoms, making them poor conductors of heat. C. Electrons are tightly bound to their atoms, making them poor conductors of heat. D. Electrons are loosely bound to their atoms, making them good conductors of heat.

C. Electrons are tightly bound to their atoms, making them poor conductors of heat.

Why are metals good conductors of both heat and electricity? A. The outer shell electrons in atoms vibrate in place and emit electromagnetic radiation that travels throughout the metal. B. The outer shell electrons in metals move with zero resistance, making all metals superconductors. C. The outer shell electrons in metals are free to move from atom to atom. D. The outer shell electrons in metals are tightly bound, making it easy for vibrations to move from one atom to the next.

C. The outer shell electrons in metals are free to move from atom to atom.

A fundamental rule of electricity is that A. like kinds of charges repel. B. unlike kinds of charges attract. C. both of these D. neither of these

C. both of these

Electric potential, measured in volts, is the ratio of electric energy to the amount of electric A. voltage. B. current. C. charge. D. resistance. E. none of the above

C. charge.

The electrical force on a 2-C charge is 60 N. The electric field where the charge is located is A. 120 N/C. B. 60 N/C. C. 240 N/C. D. 30 N/C. E. 20 N/C.

D. 30 N/C.

How does the charge of one electron compare to that of another electron? How does it compare with the charge of a proton? How do the masses of protons and electrons compare? A. All electrons and protons have exactly the same charge and mass. B. All electrons have the same charge. Electron charge is equal and opposite to the proton charge. A electron has 1800 times the mass of a proton. C. All electrons and protons have exactly the same charge. A proton has 1800 times the mass of an electron. D. All electrons have the same charge. Electron charge is equal and opposite to the proton charge. A proton has 1800 times the mass of an electron.

D. All electrons have the same charge. Electron charge is equal and opposite to the proton charge. A proton has 1800 times the mass of an electron.

What happens to electrons in any charging process? A. Electrons stay in place as protons are transferred from one place to another. B. Electrons are destroyed. C. Electrons are created. D. Electrons transfer from one place to another.

D. Electrons transfer from one place to another.

What term is used for "electricity at rest"? A. Electricity B. Current electricity C. Electrodynamics D. Electrostatics

D. Electrostatics

Between a pair of equal and opposite charges, field lines are A. directed from positive to negative. B. vectors, with patterns that stem from the inverse-square law. C. more concentrated closer to the charges. D. all of the above E. none of the above

D. all of the above

The fundamental force underlying all chemical reactions is A. gravitational. B. nuclear. C. centripetal. D. electrical. E. none of the above

D. electrical.

To become a negative ion, an atom must A. lose an electron. B. gain a proton. C. lose a proton. D. gain an electron.

D. gain an electron.

Particle A has twice the charge of nearby particle B. Compared to the force on Particle A, the force on Particle B is A. twice as much. B. half as much. C. four times as much. D. the same. E. none of the above

D. the same.

A droplet of ink in an industrial ink-jet printer carries a charge of 1.9×10−10C and is deflected onto paper by a force of 3.1×10−4N. Find the strength of the electric field to produce this force.

E = 1.6×10^6 N/C

A positive ion has more A. protons than neutrons. B. electrons than protons. C. electrons than neutrons. D. neutrons than protons. E. protons than electrons.

E. protons than electrons.