Katie rubs a balloon against her hair. Electrons from her hair travel to the balloon, giving the balloon a negative charge and her hair a positive charge. When the negatively charged balloon is brought near the strands of Katie's hair, they move to get closer to the balloon, without the balloon actually touching them. This shows that (1 point)Responses electric attraction is a force that can act at a distance. Electric attraction is a force that can act at a distance. Katie's hair would move in this way with or without the balloon. Katie's hair would move in this way with or without the balloon. Particles in the air must be pulling Katie's hair toward the balloon particles in the air must be pulling Katie's hair toward the Balloon electric attraction is a force that can only act on contact.
Electric attraction is a force that can act at a distance.
The Earth has a magnetic field around it, which is generated by its molten core. This magnetic field exerts a force on compass dials, which are magnets, causing them to align with the Earth's magnetic field.This force on compass dials is an example of a force that _______. (1 point) Responses acts only on contact. Acts only on contact. acts at a distance. Acts at a distance. Acts through particles in the air. Acts through particles in the air. Needs electricity to act.
acts at a distance.
The _______ force is a noncontact force that is created by the movement of an electrical charge. (1 Responses gravitational resistance centrifugal electromagnetic.
electromagnetic.
Nora tied a string around a tennis ball, and then she swung it in a circle in front of her to demonstrate a planet orbiting the Sun. She explained that her hand represented the Sun, the ball represented a planet, and the string kept the ball from leaving the "orbit" around her hand. Why doesn't the string work in the same way as gravity? (1 point) Responses The string only pulls one way; gravity pulls both ways. The string only pulls one way; gravity pulls both ways. The string holding the ball in orbit is a contact force; gravity is a noncontact force. The string holding the ball in orbit is a contact force; gravity is a noncontact force. The string keeps the distance between the bodies the same; gravity makes the distance vary. The string keeps the distance between the bodies the same; gravity makes the distance vary. There is no difference between the two systems.
The string holding the ball in orbit is a contact force; gravity is a noncontact force.
Astronauts on the Moon can jump higher than if they were on Earth. This is because (1 point) Responses there is no friction on the Moon there is no friction on the Moon Newton's laws of motion do not apply to the Moon. Newton's laws of motion do not apply to the Moon. The astronauts are less massive on the Moon. The astronauts are less massive on the Moon. The Moon is less massive than the Earth.
The astronauts are less massive on the Moon.
Imagine an object falling to the Earth. Which of the following most accurately describes the motion of that object? (1 point)Responses It falls toward the center of the Earth. It falls toward the center of the Earth. It falls southward. It falls southward. It falls toward the nearest solid ground. It falls toward the nearest solid ground. Its motion is random as it falls.
