Final answer:
The Cavendish experiment determined the gravitational constant, G, and faced difficulties due to the weak nature of gravity and the mass of the objects used in the experiment.
Step-by-step explanation:
Part A: The Cavendish experiment determined the gravitational constant, G. This constant is a fundamental value that helps calculate the strength of the gravitational force between objects. The Cavendish experiment determined the gravitational constant, G, and faced difficulties due to the weak nature of gravity and the mass of the objects used in the experiment.
Part B: The experiment was difficult because gravity is a very weak force, making it challenging to measure the attraction between the less massive objects used in the apparatus. Cavendish had to carefully account for any interference or disturbances that could affect the accuracy of his measurements.