A lamp of mass m hangs from a spring scale which is attached to the ceiling of an elevator. When the elevator is stopped at the fortieth floor, the scale reads mg. What does it read as the elevator slows down to stop at the ground floor? a. more than mg
b. mg
c. less than mg
d. zero
e. can't tell

The correct answer is (a)

Explanation:

A spring scale measures the weight of an object not the mass because according to hooke's law the extension of a spring is directly proportional to the load or force attached/applied to it. The force of gravity acting on the mass of any substance as it goes up actually reduces and increases as it comes down.

If F = ma, as a increases, F will also increase and vice versa

Where F = force

m = mass

a = acceleration (due to gravity in this case)

From the above explanation, it can be deduced that the scale will read more than mg as it gets to the ground because of an increase in the force of gravity (which also increases a) as it approaches the ground.

a=d/t

a="triangle"v/t

explanation:

a = acceleration