We often hear that an astronaut experiences weightlessness in space. What does this mean? Let us perform a simple experiment to demonstrate weightlessness. Suspend a stone from a spring balance, the pointer of the spring balance shows the weight of the stone. Allow the spring balance along with the stone to fall freely. The spring balance records zero weight indicating that the stone is weightless. Does it mean that the weight of the stone is zero? No, actually the stone is in the state of weightlessness as it is falling freely. A body becomes conscious of the weight, whenever its weight is opposed by some other object.
Now, let us try to explain why an astronaut in a spaceship experiences weightlessness. When the astronaut in the spaceship is orbiting the Earth, then both, the astronaut and the spaceship are in a state of free fall towards the Earth. During a free fall, both travel downwards with the same acceleration, equal to the acceleration due to gravity. As a result, the astronaut does not exert any force on the sides or floor of the spaceship, and the sides and floor of the spaceship do not push the astronaut up. The astronaut therefore experiences weightlessness while orbiting around the Earth in a spaceship.
A satellite/spaceship orbiting the Earth is actually falling freely towards the Earth.
Weightlessness and why it happens?
- It is just a feeling experienced by a separate person when there are no visible objects moving one’s body and applying a push or pull upon it. Weightlessness sense exist when all connecting forces are discarded. These senses are ordinary to any condition in which you are provisionally in a condition of free fall. When in free fall, the single force acting upon your body is the force of gravity which is a non – contact force. So, the force of gravity cannot be noticed without any other opposite forces, you have no feeling of it. You would noticed weightless when in a state of free fall.
- If you go any amusements parks for riders of roller coasters and different rides in which riders are provisionally airborne and scoop out of their seats. Assume that you were raised in the top of a very high tower and then your chair was instantly drop out. As you and your chair drop towards the ground, you both accelerate at the same rate g. the chair is movable, falling at the same rate as you, it is incompetent to push upon you. Standard forces only result from contact with steady, assisting surfaces. Gravitational force is the single force acting upon your body. There are no outermost sensation. You would consider as much as you always do yet you would not have any feeling of this weight.
Weightlessness is not only a feeling but also an unreal fit to separate who has lost weight. Ay you are free falling on a roller coaster ride in an amusement park, you have not directly lost your weight. Weightlessness has very small to do with weight and mainly to do with the existence of contact forces. The force of gravitational attraction to the Earth is referring by weight, a free – falling person has not “lost his weight”, and he is still meeting the Earth’s gravitational attraction. Woefully, the uncertainty of a person’s real weight with one’s feeling of weight is the source of mainly misunderstanding.