Johanna makes the table below to organize her notes about centripetal forces.

| Circular Motion | Centripetal Force |
|---------------------------|-------------------|
| a space station in orbit | [tex]$X$[/tex] |
| a child in a swing | |
| a ball on a string | |

Which type of force should she place in the cell marked X?

A. tension
B. gravity
C. friction
D. normal



Answer :

To determine the type of force that should be placed in the cell marked X for "a space station in orbit," we need to understand the nature of centripetal force and how it applies to an object in orbit.

Step-by-Step Explanation:

1. Definition of Centripetal Force:
Centripetal force is the force that acts on an object moving in a circular path, directed towards the center around which the object is moving. It is necessary for keeping the object in circular motion.

2. Forces in Circular Motion:
Different scenarios of circular motion have different sources of centripetal force:
- For a child in a swing, the centripetal force is provided by the tension in the ropes of the swing.
- For a ball on a string, the centripetal force is provided by the tension in the string.
- For a car turning on a flat road, the centripetal force is provided by the friction between the tires and the road.

3. Centripetal Force for a Space Station in Orbit:
In the context of an object in orbit, such as a space station, the centripetal force is provided by the gravitational pull exerted by the central body around which it is orbiting (e.g., Earth).

- Gravitational Force: This is the force of attraction between two masses. For a space station, it is the attractive force between the Earth and the space station.
- The gravitational force acts as the centripetal force that keeps the space station in its circular orbit around the Earth.

Therefore, the type of force that should be placed in the cell marked X is:

gravity

This is because gravitational force is the centripetal force that acts on the space station in orbit around the Earth, keeping it in its circular path.