Phy Science test 3

An iron rod becomes magnetic when A) the net spins of its electrons are in the same direction. B) positive ions accumulate at one end and negative ions at the other end. C) its atoms are aligned with positive charges on one side and negative charges on the other side. D) electron motion stops. E) none of the above

A

Compared to a single lamp connected to a battery, two lamps connected in parallel to the same battery will draw A) more current. B) the same current. C) less current.

A

Electric potential Energy is measured in units of A) joules. B) volts. C) amperes. D) watts.

A

Stretch a copper wire so that it is thinner and the resistance between its ends A) increases. B) remains unchanged. C) decreases.

A

The headlights, radio, and defroster fan in an automobile are connected in A) parallel. B) order of energy efficiency. C) series.

A

The nucleus of an atom is charged A) positively. B) negatively. C) both D) none of the above

A

The number of protons in the nucleus of an electrically neutral atom is equal to the number of A) electrons that surround the nucleus. B) neutrons in the nucleus. C) both D) neither

A

To say a circuit is dc is to say that current in the circuit A) has a single direction. B) is parallel to the connecting wires. C) alternates only slowly.

A

When two lamps are connected in parallel to a battery, the electric resistance that the battery senses is A) less than the resistance of either lamp. B) more than the resistance of either lamp. C) none of the above

A

A pair of positively-charged plastic straws tend to A) neutralize each other. B) repel each other. C) attract each other.

B

The electric current in a copper wire is normally composed of A) ions. B) electrons. C) protons. D) all or any of the above

B

The electric resistance of a superconductor is A) usually lower than that of ordinary resistors. B) zero. C) infinite

B

To say that an object is electrically polarized is to say A) its charges have been rearranged. B) its internal electric field is zero. C) it is only partially conducting. D) it is electrically charged.

B

To say that electric charge is conserved is to say that electric charge A) may occur in an infinite variety of quantities. B) can neither be created nor destroyed. C) will interact with neighboring electric charges. D) is a whole-number multiple of the charge of one electron.

B

When a person experiences an electric shock, the origin of the electrons comprising the shock is A) a power plant. B) the personʹs own body. C) the ground. D) likely a faulty lamp. E) the electric field in the air.

B

When you remove electrons from a metal cup, the cup becomes A) positively charged. B) ionized. C) negatively charged

B

A balloon will stick to a wooden wall if the balloon is charged A) positively. B) negatively. C) either D) neither

C

One main difference between gravitational and electric forces is that electric forces A) are weaker. B) act over shorter distances. C) repel or attract. D) attract. E) obey the inverse-square law.

C

The reason that Lillianʹs hair stands out when her hand is on a charged Van de Graaff generator is A) a high voltage is communicated to strands of hair. B) electrons and protons are deposited on her hair. C) strands of hair become charged and repel one another. D) strands of hair find themselves in an electric field.

C

Unlike electric charges, magnetic poles cannot be A) located. B) destroyed. C) isolated.

C

Which statement is correct? A) voltage flows through a circuit B) resistance is established across a circuit C) charge flows through a circuit D) current causes voltage

C

A negatively-charged balloon touching a wooden wall A) pushes negative charge in the wall away from it. B) pulls positive charge on the wall surface toward it. C) polarizes molecules in the wall. D) all of the above E) none of the above

D