Norah 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 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. There is no difference between the two systems. There is no difference between the two systems. The string only pulls one way; gravity pulls both ways. The string only pulls one way; gravity pulls both ways. The string keeps the distance between the bodies the same; gravity makes the distance vary.

Answer 1

The correct response is: The string holding the ball in orbit is a contact force; gravity is a noncontact force.

This response accurately highlights the fundamental difference between how the string and gravity operate. The string physically connects Norah's hand (representing the Sun) to the tennis ball (representing the planet), exerting a force through contact. In contrast, gravity acts at a distance without any physical connection, pulling objects towards each other due to their masses.