Unit D - Section 1 and 2 Test

A definition of static electricity is

• the loss of electric charges from an object

• the build up of electric charges on an object

• the sharing of electric charges between objects

• the transfer of electric charges between objects

One evening while you are out for a walk, it starts to rain and you see a bolt of lightning flash across the sky. Lightning is an example of:

• current electricity flowing between the clouds and ground

• current electricity building up inside the clouds

• static electricity being discharged through the air

• static electricity building up in rain clouds

Which unit is used to measure the rate at which an electrical current flows?

• ampere

• ohm

• watt

• volt

You attach a small light bulb to the negative terminal of a battery but the light does not work. You then attach a second wire from the light bulb to the positive terminal of the same battery. Why is this second wire necessary?

• The electrons from the battery must be allowed to flow through the light bulb along two different paths.

• The electrons must continually flow from both the positive and negative terminal to light the bulb.

• The electrons must be allowed to flow from the positive terminal of the battery to the light bulb.

• The electrons need a complete circuit from the negative terminal to the positive terminal.

The seriousness of an electrical shock depends not only on the voltage and current, but also on the material through which the electricity is passing. Which situation would result in the most serious shock?

• touching an electric fence while standing on a block of wood

• touching an electric fence while standing on grass in bare feet

• touching an electric fence while wearing a pair of rubber boots

• touching an electric fence while standing in water wearing sandal

While golfing one afternoon, you notice a rainstorm moving toward the golf course. You see lightning and hear the thunder. What would be the safest place to wait out the storm and avoid being struck by lightning?

• huddled beside a metal maintenance shop near one of the holes

• lying flat on the ground in the middle of an open fairway on the golf course

• sitting in your golf cart on a hill in the middle of the golf course

• kneeling down under the trees surrounding one of the golf holes

An electrochemical cell can be used to provide many devices with energy to operate. What energy conversion takes place in an electrochemical cell?

• electrical energy to chemical energy which is then used by the device

• chemical energy to electrical energy which is then used by the device

• electrical energy into any form of energy required by the device

• chemical energy into any form of energy required by the device

You buy a new portable stereo and the manual states that you must use eight 1.5-V cells. You thought that you would need to use batteries; and you are unsure of what cells are. When you tell your parents, they explain that the difference between cells and batteries is

• batteries last longer than cells

• batteries are made up of two or more cells

• batteries produce a maximum of 1.0 V of energy

• batteries produce a maximum of 1.0 V of energy

In science class, you learned that a conductor is a material that passes electrons easily and that an insulator is a material that does a poor job of conducting (or passing) electrons. How are the electrons in an insulator different from the electrons in a conductor?

• The electrons in an insulator are tightly bound to the positively charged nucleus.

• The electrons in an insulator are tightly bound to the positively charged nucleus.

• The electrons in an insulator flow toward the negative terminal.

• There are no electrons present in insulating materials

Resistance is a measure of how difficult it is for electrons to flow through a substance. The unit used for measuring resistance is the:

• volt

• ampere

• ohm

• joule