Which of the following quantities are not vectors?
Select one: a. force b. velocity C energy d. momentum
The correct answer and explanation is:
The correct answer is c. energy.
Explanation:
A vector is a physical quantity that has both magnitude and direction. Vectors are typically represented by arrows, where the length represents the magnitude, and the direction indicates the direction of the quantity.
- Force: This is a vector quantity because it has both magnitude and direction. The force acting on an object can be described by how much force is applied and in which direction it is applied (e.g., a force of 10 Newtons to the right).
- Velocity: This is also a vector quantity. Velocity describes the speed of an object and the direction in which it is moving. For instance, an object moving at 20 meters per second to the north has both a magnitude (speed) and a direction.
- Energy: Energy, on the other hand, is a scalar quantity. It is defined as the capacity to do work, and it only has magnitude, not direction. For example, an object can have 50 joules of energy, but energy does not require any directional specification, making it a scalar quantity.
- Momentum: Momentum is a vector quantity. It is the product of an object’s mass and its velocity. Since velocity is a vector, momentum also has both magnitude and direction. For instance, a moving car with a certain mass and speed will have momentum in the direction it is moving.
In summary, energy is the only quantity in this list that does not have a direction, making it a scalar quantity, while force, velocity, and momentum are all vector quantities due to their dependence on both magnitude and direction.