Unit 2 Lesson 5 - Electricity

What is an electric charge?

• Fundamental property of matter that causes electric phenomena

• Electric charge is a type of magnetic field

• Electric charge is a unit of currency

• Electric charge is a type of battery

During a science fair, William and Benjamin are demonstrating an experiment on static electricity. They explain that there are two kinds of electric charge involved in their experiment. What are these two charges?

• Positive and positive

• Negative and neutral

• Charged and uncharged

• Positive and negative

A neutral object is an object that has what?

• An equal number of positive and negative charges

• An unequal number of positive and negative charges

• Magnetic field

• Positive charge

Attractive or repulsive noncontact forces between charged particles is called this.

• electric force

• frictional force
• nuclear force
• gravitational force

When do balloons repel each other?

• When both balloons are rubbed with wool and have the same charge

• When both balloons are not rubbed and are neutral

• When one balloon is rubbed with silk and the other with wool, having opposite charges

• When both balloons are touching each other

At a school science fair, Nora and Evelyn are demonstrating how different types of molecules interact. Which of the following setups are likely to demonstrate attractive forces?

• Two balloons that both have no charge

• Two balloons that both have negative charges

• Two balloons that both have positive charges

• Two balloons with one having a negative charge and one having a positive charge

An object with a lot of charge is likely to?

• Exert a small electric force

• Repel objects with the same charge
• Create a magnetic field around itself
• Exert a large electric force

Emma is working on a science project about electric fields. Which of the following statements would be true for her project?

• An electric field only exists in a vacuum

• Electric fields can be used to predict the electric force exerted on a negatively charged test object

• An electric field is a scalar quantity

• Electric fields can be used to predict the electric force exerted on a positively charged test object

Which of the following is true of a test object used by Daniel in his physics experiment?

• It indicates the amount of charge an object has

• It is an imaginary object with 1 N of charge

• It predicts how much charge an object will gather

• It is an imaginary object with 1 C of charge

In what situation does a charged object create an electric field?

• When it is stationary and isolated from other objects

• When it is in a vacuum

• When it is in motion but not interacting with any objects

• It always creates an electric field