Weight (Edexcel IGCSE Physics)

NASA's Artemis mission aims to send the first woman astronaut to the Moon. Isabelle hopes to one day become an astronaut. She has a mass of 40 kg.

Take the Earth's gravitational field strength as 10 N/kg, and the Moon's gravitational field strength as 2 N/kg.

Comment on the difference between Isabelle's weight on Earth, and her weight on the Moon. 

 

Answer:

 

Step 1: State the equation linking weight and mass

• • The equation linking weight and mass is:

W = m × g

Step 2: List the known values

• • The question instructs us to take the Earth's gravitational field strength as 10 N/kg
  • The question also instructs us to take the Moon's gravitational field strength as 2 N/kg
  • Mass, m = 40 kg

Step 3: Calculate Isabelle's weight on Earth

• • Substituting the values of mass and Earth's gravitational field strength into the equation gives:

W = 40 × 10 = 400 N

Step 4: Calculate Isabelle's weight on the Moon

• • Substituting the values of mass and the Moon's gravitational field strength into the equation gives:

W = 40 × 2 = 80 N

Step 5: Comment on the two values of weight

• • Isabelle's weight is greater on Earth than on the Moon
  • This is because the Earth has a larger gravitational field strength than the Moon, so Isabelle's weight force (the force of gravity pulling down on her) is larger on Earth than on the Moon