Which expression correctly defines the Newton in base SI units?

Which expression correctly defines the Newton in base SI units?

• A. kg × m/s^2
• B. J × s
• C. Pa × m
• D. kg × m^2/s^2

Answer: (A)

The Newton is a unit of force, defined by F = m a, where mass times acceleration gives force. In base SI units, mass is in kilograms and acceleration is in meters per second squared, so the Newton is kg·m/s^2. This matches the idea that a force of 1 Newton acting on a 1 kilogram mass produces an acceleration of 1 m/s^2. Other expressions don’t represent force in base units: kg·m^2/s^2 is a joule (unit of energy), Pa·m simplifies to a unit combining pressure and length that isn’t force, J·s is action, and kg·s^-2 lacks the length dimension needed for force.

The Newton is a unit of force, defined by F = m a, where mass times acceleration gives force. In base SI units, mass is in kilograms and acceleration is in meters per second squared, so the Newton is kg·m/s^2. This matches the idea that a force of 1 Newton acting on a 1 kilogram mass produces an acceleration of 1 m/s^2.

Other expressions don’t represent force in base units: kg·m^2/s^2 is a joule (unit of energy), Pa·m simplifies to a unit combining pressure and length that isn’t force, J·s is action, and kg·s^-2 lacks the length dimension needed for force.