Question

In the International Space Station which orbits Earth, astronauts experience apparent weightlessness because

(a) the station is so far away from the center of the Earth.

(b) the station is kept in orbit by a centrifugal force that counteracts the Earth's gravity.

(c) the astronauts and the station are in free fall towards the center of the Earth.

(d) there is no gravity in space.

(e) the station's high speed nullifies the effects of gravity.

Short answer

The correct option is (c) the astronauts and the station are in free fall towards the center of the Earth.

Step-by-step solution

Step 1. Understanding the motion of the space station around the Earth

The space station and the astronauts experience the centripetal acceleration towards the Earth. And due to gravitational force, the space stations revolve around the Earth. Without these forces, they will follow a straight-line path.

Step 2. Determination of the correct option

The gravitational force on the space station provides the orbital motion around the Earth.

The normal force applied by the astronauts on the station will be equal to zero.

So, the astronaut’s apparent weight will also be zero.

At every point of the motion, the Astronaut and the station fall freely towards the Earth due to its gravitational pull; that's why they feel apparent weightlessness.

Other statements in the options are not the correct reason for the apparent weightlessness.

Thus, the correct option is (c).