Photo AI

Define gravitational potential at a point - AQA - A-Level Physics - Question 3 - 2019 - Paper 2

Question icon

Question 3

Define-gravitational-potential-at-a-point-AQA-A-Level Physics-Question 3-2019-Paper 2.png

Define gravitational potential at a point. 0 3 . 2 Figure 2 shows the positions of equipotential surfaces at different distances from the centre of the Moon. Exp... show full transcript

Worked Solution & Example Answer:Define gravitational potential at a point - AQA - A-Level Physics - Question 3 - 2019 - Paper 2

Step 1

Define gravitational potential at a point.

96%

114 rated

Answer

Gravitational potential at a point is defined as the work done per unit mass in bringing a small test mass from infinity to that point against the gravitational field.

Step 2

Explain how the equipotential surfaces in Figure 2 show that the gravitational field is not uniform.

99%

104 rated

Answer

The equipotential surfaces in Figure 2 show variations in gravitational potential at different distances from the Moon's center. As the distance from the center of the Moon increases, the spacing between the equipotential surfaces decreases, indicating that the gravitational field strength changes. The non-parallel lines signify that the gravitational force is stronger closer to the Moon and weaker further away.

Step 3

Calculate, using Figure 2, the escape velocity at the surface of the Moon.

96%

101 rated

Answer

To calculate the escape velocity ( vev_e ) at the surface of the Moon, we use the formula: ve=2ghv_e = \sqrt{2gh} where:

  • gg is the gravitational acceleration at the surface, and
  • hh is the height, which is equivalent to the radius of the Moon.

From Figure 2, we can infer gg using the potential difference between equipotential surfaces: g=ΔVΔrg = -\frac{ΔV}{Δr} Using the values: r=1.74×106extmr = 1.74 × 10^6 ext{ m} we find: ve=2imes2.4×102extm/s2×1.74×106extmv_e = \sqrt{2 imes 2.4 × 10^2 ext{ m/s}^{2} \times 1.74 × 10^6 ext{ m}} After calculating, ve2.3×103extm/sv_e ≈ 2.3 \times 10^{3} ext{ m/s}.

Join the A-Level students using SimpleStudy...

97% of Students

Report Improved Results

98% of Students

Recommend to friends

100,000+

Students Supported

1 Million+

Questions answered

;