Topic 3 Quiz

Which one of the following statements is NOT correct about gravity?
1. It is an attractive force
2. It has an infinite range
3. It is a very tiny force
4. It is both attractive and repulsive
Gravity is felt in the vicinity of planets and stars. This is because:
1. Planets and stars have magnetic fields.
2. Planets and stars are very large objects.
3. Planets and stars rotate, causing a centripetal force.
4. Planets and stars go about in groups
A comet is travelling in a certain direction. It experiences a gravity force at 90 degrees to its direction of movement as it passes a star. Which one of these is most likely to happen?
1. It will go into orbit round the star.
2. It continue in a straight line
3. It will crash into the star
4. It will break up.
What is the shape of a normal orbit of a planet around a star?
1. A perfect circle.
2. A spiral
3. An ellipse
4. A random orbit.
Which one of these statements about planets orbiting stars is correct?
1. The orbital period decreases the further the planet is from the star.
2. Gravity provides the centripetal force to keep the planet in orbit.
3. Planets rotate faster on their axes the closer they are to a star.
4. Other forces apart from gravity are involved in keeping planets in orbit.
A satellitel stays in orbit above the Earth because:
1. Centrifugal force keeps it there.
2. There is zero gravity
3. Gravity is providing the centripetal force to keep it there.
4. There is a rocket motor keeping it flying in orbit
Which way does gravity on a planet act?
1. From left to right.
2. From right to left.
3. Always away from the centre of the planet.
4. Always towards the centre of the planet.
A satellite fires its rocket motor to make it go faster. Which one of these correctly describes what will happen?
1. It will go faster in a higher orbit.
2. It will go faster in the same orbit.
3. It will go faster in a lower orbit.
4. It will crash to the ground.
Which one of these statements is correct about a satellite in geostationary orbit?
1. It orbits the Earth every 90 minutes in the same direction as the Earth's rotation.
2. It orbits the Earth every 90 minutes in the opposite direction to the Earth's rotation.
3. It orbits the Earth every 24 hours in the same direction as the Earth's rotation.
4. It orbits the Earth every 24 hours in the opposite direction to the Earth's rotation.
Which one of these is NOT a use for a satellite in low polar orbit?
1. Communication
2. Weather monitoring
3. Spying on a hostile country.
4. Monitoring the drift of smoke from a forest fire.