Question

A book placed on a balance scale is balanced by a standard 1-kg iron weight placed on the opposite side of the balance. If these objects are taken to the moon and a similar exercise is performed, the balance is still level because gravity is uniform on the moon’s surface as it is on Earth’s surface.

A. True
B. False

Answer 1

The statement is false because weight is dependent on local gravity, but a balance scale measures mass, not weight. The balance would still level out on the Moon since the mass of the book and the 1-kg weight remain the same, even though the gravitational force is different.

Step-by-step explanation:

The statement is False. While mass remains constant regardless of location, weight is a function of both mass and the acceleration due to gravity (g). On Earth, g is approximately 9.80 m/s². On the Moon, however, g is significantly less, about 1.67 m/s². Thus, an object's weight on the Moon is much less than its weight on Earth. The balance still levels out on the Moon because a balance scale measures mass, not weight, and the masses of the book and the 1-kg standard iron weight haven't changed.

Since mass is an intrinsic property of an object and does not change with location, the mass of the 1-kg iron weight and that of the book remain the same on the Moon as on Earth. However, the weight - the gravitational force acting on the mass - would change due to the Moon's lower g. When people refer to 'losing weight' on Earth, they usually mean losing mass, which indirectly reduces their weight due to the constant Earth's gravity.

Balance scales compare mass directly and do not measure the gravitational force acting on the objects. Therefore, the scale will balance on the Moon for the same reason it balances on Earth: the masses of the book and the 1-kg weight are equal, despite the difference in gravitational force.