Questions on the Earth in Space
Q17.
A writer of science fiction likes to make her stories as realistic as possible. In her latest book there is a group of space travellers who discover a star in a distant part of the galaxy. The travellers are excited to find a planet very similar to Earth orbiting this star. They call the planet Delta. The table compares data about Delta and the Earth. Most of the figures are relative.
|
Delta |
Earth |
The planet's distance from the star it orbits. |
1.5 |
1 |
Mass of the planet |
1.5 |
1 |
Average density of the planet |
1 |
1 |
Time for the planet to rotate once on its own axis |
0.85 |
1 |
Speed of the planet in its orbit |
0.82 |
1 |
Angle of tilt of the planet's axis |
23o |
0o |
Acceleration of an object freely falling near to the planet's surface |
11 m/s2 |
10 m/s2 |
(a) In her story, how should the writer compare conditions on Delta with those on Earth? Tick the correct box in each case.
|
greater |
less |
same |
length of year |
|
|
|
length of day |
|
|
|
radius of the planet |
|
|
|
3 marks
(b) One of the space travellers lands on planet Delta. With her space suit, she has a mass of 100 kg. What is her weight on planet Delta? Don't forget to give the unit.
2 marks
(c) The inclination of the axis of rotation to the axis of orbit (the 'tilt' of the planet) is different for Delta and Earth.
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In the story, the travellers spend a year on Delta. Describe two differences between Delta and Earth that the travellers would find, apart from their weight.
2 marks
Maximum 7 marks
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