Question

When a forklift raises an object, is it doing positive or negative work on the object? Which type of work is the force of gravity doing on the object? a)The forklift is doing negative work on the object because the direction of force and the direction of motion are the same. The force of gravity is doing positive work on the object because it is acting opposite to the direction of motion. b)The forklift is doing positive work on the object because the direction of force and the direction of motion are the same. The force of gravity is doing negative work on the object because it is acting opposite to the direction of motion. c)The forklift is doing positive work on the object because the direction of force and the direction of motion are the same. The force of gravity is doing positive work on the object because it is acting opposite to the direction of motion. d)The forklift is doing negative work on the object because the direction of force and the direction of motion are the same. The force of gravity is doing negative work on the object because it is acting opposite to the direction of motion.

Answer 1

Answer: B

The forklift is doing positive work on the object because the direction of force and the direction of motion are the same. The force of gravity is doing negative work on the object because it is acting opposite to the direction of motion. 

Explanation: The work done in lifting an object up is positive when the direction of the displacement and the force applied are in the same direction.

The work will be negative if force and direction of the motion are opposite to each other.

Also, force of gravity is considered positive when an object is moving toward the gravity. That is coming downward. Otherwise, it's negative when it's moving in the opposite direction.

When a forklift raises an object, the forklift is doing positive work on the object because the direction of force and the direction of motion are the same. The force of gravity is doing negative work on the object because it is acting opposite to the direction of motion.