Is an astronaut in space completely weightless? Explain your answer.
No, an astronaut in space is not completely weightless. While it is true that astronauts experience a sensation of weightlessness in space, they are still subject to the effects of gravity. Weightlessness occurs because astronauts are in a constant state of freefall around the Earth.
The feeling of weightlessness is a result of the spacecraft and everything inside it falling towards Earth at the same rate. This creates a perpetual state of freefall, where objects and astronauts appear to be floating. However, the gravitational force is still acting upon them.
In Earth's orbit, the force of gravity is still significant but constantly pulling astronauts towards the Earth's center. The reason they don't fall is that their forward motion provides the necessary speed to keep them in orbital motion. This balance between gravity pulling them towards Earth and their forward velocity creates the feeling of weightlessness.
So while astronauts experience a sense of weightlessness due to their perpetual freefall, they are still subject to the force of gravity.