靜電與電場：练习题

• a.

  Protons in the wall's surface are attracted toward the balloon, creating a positive charge layer.

• b.

  Electrons jump from the balloon to the wall, making the wall negatively charged.

• c.

  The balloon becomes neutral as it approaches the wall due to earthing through the air.

• d.

  Electrons in the wall's surface are repelled away from the balloon, leaving the surface with a net positive charge.

• a.Positive ions move through the copper wire into the ground
• b.\(4.0 \times 10^{-3}\) protons move from the sphere to the Earth
• c.\(2.5 \times 10^{16}\) electrons move from the Earth to the sphere
• d.\(2.5 \times 10^{16}\) electrons move from the sphere to the Earth

• a.

  The lines are radial, point towards the charge, and are more concentrated closer to the charge.

• b.

  The lines are parallel and equally spaced, indicating a uniform field strength.

• c.

  The lines form concentric circles around the charge, showing the direction of rotation.

• d.

  The lines are radial, point away from the charge, and are more concentrated closer to the charge.

• a.

  It increases the resistance between the tanker and the aircraft to stop current flow.

• b.

  It converts the static electricity into useful chemical energy for the fuel.

• c.

  It ensures that both the tanker and the aircraft become highly positively charged to repel the fuel.

• d.

  It ensures there is no potential difference between the tanker and the aircraft by allowing charge to flow between them.

• a.

  Protons are transferred from the cloth to the rod.

• b.

  Electrons are transferred from the cloth to the rod.

• c.

  Protons are transferred from the rod to the cloth.

• d.

  Electrons are transferred from the rod to the cloth.

先自己写一遍答案，再对照解题步骤。