The kilogram per meter squared per second squared is the SI unit of acceleration, momentum, force, and speed.
The correct answer and explanation is:
Correct Answer: Force
The kilogram meter per second squared (kg·m/s²) is the SI unit of force, also known as the newton (N). This unit measures the amount of force required to accelerate a mass of one kilogram at a rate of one meter per second squared. The formula for force is derived from Newton’s second law of motion:
Force = mass × acceleration
F = m × a
When the mass is in kilograms and the acceleration is in meters per second squared, the resulting unit becomes:
kilogram × meter per second squared = kg·m/s²
This is defined as one newton, the SI derived unit of force. The newton is used in physics and engineering to quantify force applied on objects, including gravitational force, frictional force, tension, and others.
To understand why this unit does not represent acceleration, momentum, or speed:
- Acceleration is measured in meters per second squared (m/s²), not in kilograms.
- Momentum is measured in kilogram meters per second (kg·m/s), which reflects the product of mass and velocity.
- Speed or velocity is measured in meters per second (m/s), which is the distance covered per unit time.
Only force uses the unit kg·m/s², because it represents a mass being accelerated. For example, pushing a 2-kilogram object to accelerate at 3 m/s² involves a force of:
F = 2 kg × 3 m/s² = 6 N
In summary, the kilogram meter per second squared is exclusively the SI unit of force, and it plays a central role in understanding motion and the application of energy in mechanics.