Weight, mass and gravitational field strengthIB MYP Physics: Subtopic test

1. 1
   An astronaut of mass 60 kg is training for a mission to the Moon. The gravitational field strength is 10 N/kg on Earth and 1.6 N/kg on the Moon.

   (a)

   Which quantity stays the same for the astronaut when she travels from Earth to the Moon?

   [1 mark]

   • AHer weight
   • BThe force of gravity on her
   • CHer mass
   • DThe gravitational field strength around her

   (b)

   What is the astronaut's weight on the Moon?

   [1 mark]

   • A96 N
   • B37.5 N
   • C600 N
   • D960 N

   (c)

   Explain why the astronaut's mass is the same on the Moon, but her weight is different.

   [2 marks]

   Total for question 1: 4 marks

2. 2
   A space probe carries a standard mass of 2.0 kg on a newton meter to measure the gravitational field strength at different places. On Earth the newton meter reads 20 N. Near Jupiter it reads 50 N.

   (a)

   What is meant by a gravitational field?

   [1 mark]

   • AA region where magnetic materials feel a force
   • BA region where a mass experiences a force because of gravity
   • CThe amount of matter in an object
   • DThe force needed to lift an object at constant speed

   (b)

   What is the gravitational field strength near Jupiter?

   [1 mark]

   • A100 N/kg
   • B10 N/kg
   • C2.5 N/kg
   • D25 N/kg

   (c)

   Describe how a newton meter is used to find the weight of the standard mass.

   [2 marks]

   Total for question 2: 4 marks

3. 3
   A group of students investigates the relationship between mass and weight on Earth. They hang masses of 0.1, 0.2, 0.3, 0.4 and 0.5 kg from a newton meter. The readings are 1.0, 2.0, 3.1, 4.0 and 5.0 N.

   (a)

   Describe the trend in the results and calculate the value of weight ÷ mass for the 0.4 kg mass.

   [3 marks]

   (b)

   State what the value of weight ÷ mass represents, evaluate whether the results support the hypothesis that weight is directly proportional to mass, and suggest one improvement to the method.

   [4 marks]

   Total for question 3: 7 marks

4. 4
   A space agency is planning a permanent base on the Moon, where the gravitational field strength is 1.6 N/kg (10 N/kg on Earth). A rover and its equipment have a total mass of 100 kg. Some scientists argue that low gravity would make launching spacecraft from the Moon cheaper, but others warn that astronauts living there for years could suffer health problems.

   (a)

   Calculate the weight of the equipment on Earth and on the Moon, and explain why it is easier to lift on the Moon although its mass is unchanged.

   [6 marks]

   (b)

   Discuss and evaluate whether the agency should build a permanent Moon base.

   [6 marks]

   Total for question 4: 12 marks

End of questions