The diagram shows equipotential lines near a group of asteroids - AQA - A-Level Physics - Question 15 - 2018 - Paper 2

To determine the direction of the gravitational field at point X, we need to recall that the gravitational field lines point from regions of higher potential to regions of lower potential. In this diagram, the equipotential lines indicate that the potential decreases as we move upward.

At point X, we are situated between the equipotential lines of

-2.0 x 10⁻⁹ J kg⁻¹ (below X) and -2.5 x 10⁻⁹ J kg⁻¹ (above X).

Thus, the gravitational field at point X will point downwards, since it moves from the higher potential (-2.0 x 10⁻⁹ J kg⁻¹) to the lower potential (-2.5 x 10⁻⁹ J kg⁻¹). Therefore, the correct answer is:

B (↓)