7.1.3 Weightlessness Flashcards
Weightlessness
- The weight of astronauts in the space shuttle is 92% of their weight on Earth.
- The force, N, that a scale applies to a person is her apparent weight.
- The apparent weight of any object in free fall is zero.
A moon is orbiting a planet at a constant distance of 4.010^8 m with a speed of 950 m/s. If the density of the planet is 5.5 g/cm^3 and the mass of the moon is 7.3510^22 kg, what must the radius of the planet be in order for there to be no net force exactly 1/4 of the distance between the two?
3.1*10^3 km
In a moving elevator your apparent weight…
increases as the elevator goes up.
You are in an airplane flying over the ocean. How could you most accurately determine your distance from the water?
Stand on a scale and find the force of gravity on your mass. Then use Newton’s law of gravitation to calculate your distance from the center of the Earth. Subtract this distance from the Earth’s radius.
The average distance between Earth and the Moon is 3.8410^8m. How far from the Earth must a satellite be to have no apparent weight because of the opposing gravitational forces of Earth and the Moon?
^ is 6.6710^-11 Nm^2/kg^2 and the mass of the Earth and Moon are 5.9710^24 kg and 7.2510^22 kg, respectively.
3.46*10^8 m
A space shuttle is orbiting the Earth at a distance of 2.00*10^7 m from the Earth’s center. Assuming a circular orbit, find the shuttle’s velocity.
4.46*10^3 m/s
a 300 kg meteorite is in circular motion orbiting faraway planet with a speed of 7000 m/s. Its orbit radius is 2.0010^8 m. The planet is composed mostly of an unknown element. The radius of the planet is 110^6 m. Determine the average density of the element in g/cm^3. G is 6.67*10^-11 Nm^2/kg^2
3.51 × 10^4 g / cm^3
If the mass of a planet is 1.3810^25 kg and it’s radius is 4.3010^7 m. An apple sitting on the planet’s surface has a mass of 0.02kg. Find the acceleration of gravity on the surface of the planet.
0.50 m / s^2
