Edxecel IGCSE orbits and orbital speed

1 Which of the following celestial bodies is in our Solar System?

• A the Milky Way

• B Saturn

• C Betelgeuse

• D a black hole

Which force keeps the planets in orbit around the Sun?

• A gravitational force

• B air resistance

• C frictional force

• D repulsive force from the Sun

The size of the force acting between two objects is dependent on the separation of the two objects. What other factor impacts the size of the force between orbiting bodies?

• A the circumference of the orbiting bodies

• B the mass of the orbiting bodies

• C the volume of the orbiting bodies

• D the density of the orbiting bodies

If the Earth were to double its mass, what would the impact on the gravitational force felt on Earth be?

• A It would halve.

• B It would double.

• C It would increase.

• D It would stay the same.

Which of the following planets feels the weakest pull from the Sun?

• A Neptune

• B Mercury

• C Venus

• D Earth

Which of the following statements about a comet and its orbit is not correct?

• A It has a very elliptical orbit.

• B It travels faster the closer it is to the Sun.

• C The tail of the comet always points away from the Sun.

• D Comets orbit planets and not the Sun.

Which of the following statements about moons is not correct?

• A They emit their own light.

• B They have circular orbits.

• C They are an example of a satellite.

• D Some planets have more than one moon.

A satellite travels at a speed of 5000 m/s around the Earth. What is the time period of the orbit if the satellite is 200 km above the Earth’s surface? The radius of the Earth is 6400 km.

• A 8200 hours

• B 2.3 hours

• C 138 hours

• D 8.29 hours

A geostationary satellite has a time period of 24 hours and stays fixed above the Earth’s surface at 35 000 km. Using the Earth’s radius of 6400 km, what is the satellite’s speed above the Earth?

• A 9000 km/hr

• B 964 000 km/hr

• C 11 000 km/hr

• D 1700 km/hr