Electric Charge and Force

A neutral atom always has

• more neutrons than protons.

• the same number of protons as electrons.

• more protons than electrons.

• the same number of neutrons as protons.

Tags

NGSS.HS-PS1-7

Two unknown neutral substances are rubbed together. During the process the first substance becomes positively charged and the second substance

• acquires a positive charge.

• remains neutral.

• acquires a negative charge.

• could either be positively charged or negatively charged.

Tags

NGSS.MS-PS2-5

Two charges, each q, are separated by a distance r, and exert mutual attractive forces of F on each other. If both charges become 3q and the distance becomes 3r, what are the new mutual forces?

• 9F/9

• 2F/4

• 4F/16

• 3F/9

Two isolated charges, + 3q and - 3q, are 6 cm apart. If 3F is the magnitude of the force acting on charge - 3q, what is the magnitude and direction of the force acting on charge + 3q?

• 4F, Toward charge - 3q

• 3F, Toward charge - 3q

• 5F, Away from charge

• 8F, Away from charge - 3q

Tags

NGSS.HS-PS2-4

A negatively charged rod is brought near one end of an uncharged metal bar. The end of the metal bar farthest from the charged rod will be charged

• positive

• neutral

• negative

• none of the other answer choices are correct

Two identical conducting spheres are separated by a distance. Sphere A has a net charge of 5 µC and sphere B has a net charge of 1 µC. If the spheres touch and are moved apart, the net charge on Sphere A will be:

• 10 µC

• 3 µC

• –6 µC

• –5 µC

Tags

NGSS.HS-PS3-5

Sphere A carries a net charge and sphere B is neutral. They are placed near each other on an insulated table. Which statement best describes the electrostatic force between them?

• There is no force between them since one is neutral.

• There is a force of attraction between them.

• There is a force of repulsion between them.

• The force is attractive if A is charged positively and repulsive if A is charged negatively.

Tags

NGSS.HS-PS2-4

Sphere A carries a net positive charge, and sphere B is neutral. They are placed near each other on an insulated table. Sphere B is briefly touched with a wire that is grounded (see picture). Which statement is correct?

• sphere B remains neutral

• sphere B is now negatively charged

• sphere B is now positively charged

• sphere B is now positive and sphere A is negative

Tags

NGSS.HS-PS2-4

Two positive charges A and B are placed at the corners of equilateral triangle. What is the direction of the net electric force on charge –Q located at point C?

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Tags

NGSS.HS-PS3-5

Two positive charges A and B are placed at the corners of equilateral triangle. What is the direction of the net electric force on charge –Q located at point C?

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