Propertie of Charges

Multiple Choice

As an object acquires a positive charge, its mass usually

• decreases

• increases

• stays the same

• becomes negative

Multiple Choice

Three identical conducting spheres, S1, S2, and S3, are supported by insulating thread, as shown above. Initially, sphere S1 has a net positive charge and the other two spheres are uncharged. Spheres S1 and S2 are brought into contact and then separated. Next, spheres S2 and S3 are brought into contact and then separated. Which of the following shows the signs of the final net charges on the spheres?

Multiple Choice

Conducting spheres 1 and 2 are initially uncharged, and sphere 1 is connected to ground. A rod carrying positive charge is brought near the right side of sphere 2. The ground is disconnected and then the rod is removed. Which of the following represents the resulting charge distribution on the two spheres?

Multiple Select

Balloons 1 and 2 are tied to strings attached to a table and are attracted to each other, as shown in the figure. Balloon 1 has no net charge. Which of the following statements about the balloons are correct? Select two answers.

• Balloon 2 must be positively charged because 

        it must be attracting electrons in the atoms of

        balloon 1.

• Balloon 2 can have either a net positive charge

      or a net negative charge.

• Balloon 2 exerts an electric force on balloon 1

       because it induces charge separation in

       balloon

• Balloon 2 does not exert an electric force on   

      balloon 1 because balloon one has zero net

      charge.