1. 1
   A robotic lander with a mass of 300 kg travels from the surface of the Earth to the surface of the Moon. The gravitational field strength on the Moon's surface is about one-sixth of that on the Earth's surface. Mission engineers must recalculate the lander's weight before it touches down.

   (a)

   Which statement correctly compares the lander's mass and weight on the Moon with its mass and weight on the Earth?

   [1 mark]

   • AThe lander's mass is the same on the Moon and Earth, but its weight on the Moon is about one-sixth of its weight on Earth
   • BThe lander's mass on the Moon is one-sixth of its mass on Earth, and its weight is unchanged
   • CBoth the lander's mass and its weight are one-sixth of their Earth values on the Moon
   • DThe lander's mass and weight are both unchanged between the Earth and the Moon

   (b)

   Taking the gravitational field strength on Earth's surface as $g = 10\,\text{N/kg}$, what is the weight of the 300 kg lander while it is still on the Earth's surface, before launch?

   [1 mark]

   • A30 N
   • B300 N
   • C3000 N
   • D30000 N

   (c)

   The Moon has a much smaller mass than the Earth. Explain why this results in the Moon having a smaller gravitational field strength than the Earth, and state what effect this has on the weight of an object of a given mass placed on the Moon's surface compared with the Earth's surface.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   A school astronomy club is building a scale model of the Solar System using balls placed along a school corridor, with a large ball representing the Sun fixed at one end. They research historical models of the Solar System before deciding how to arrange the other bodies.

   (a)

   Which of the following lists the four bodies in the correct order of increasing distance from the Sun?

   [1 mark]

   • AMars, Earth, Venus, Mercury
   • BVenus, Mercury, Mars, Earth
   • CEarth, Mercury, Venus, Mars
   • DMercury, Venus, Earth, Mars

   (b)

   One club member wants to include a small icy body with a long, elliptical orbit that develops a visible tail as it approaches the Sun. Which type of Solar System object should they add to the model?

   [1 mark]

   • AAn asteroid
   • BA comet
   • CA dwarf planet
   • DA natural satellite

   (c)

   During their research, the club finds that ideas about the structure of the Solar System have changed considerably over time. Describe how this understanding has changed, referring to the position of the Earth relative to the Sun.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   A communications satellite is placed in a stable circular orbit around the Earth. Engineers later consider moving it to a new stable orbit that is closer to the Earth.

   (a)

   A communications satellite moves at a constant speed in a circular orbit around the Earth. Explain why the satellite's velocity is continuously changing even though its speed stays constant, and identify the force responsible for keeping it in this circular path.

   [3 marks]

   (b)

   The engineers decide to move the satellite into a new stable circular orbit that is closer to the Earth than its original orbit. Explain, in qualitative terms, how the satellite's orbital speed must change for the new, smaller orbit to remain stable, and why this change is necessary.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A group of students is comparing the Sun with a much more massive star recently observed by astronomers, which is expected to end its life very differently from the Sun. They also discuss two competing scientific theories about the origin of the whole Universe.

   (a)

   Describe the life cycle of a star of similar mass to the Sun, from its formation to its final stable stage, naming each stage in order.

   [6 marks]

   (b)

   Explain how the life cycle of a star with a mass much larger than the Sun differs from that of a Sun-like star, and describe how evidence such as red-shift supports the Big Bang theory of the origin of the Universe over the Steady State theory.

   [6 marks]

   Total for question 4: 12 marks

End of questions