Weight is a vector quantity with both magnitude and direction, acting towards the center of the Earth.
The formula for weight is $W = mg$, where $W$ is weight, $m$ is mass, and $g$ is gravitational acceleration (approximately $9.8 \frac{m}{s^2}$ on Earth).
Weight varies depending on the gravitational field strength of a celestial body; an object weighs less on the Moon than on Earth.
The weight of an object can be measured using a spring scale or a digital scale calibrated for gravitational force.
Normal force often counteracts weight in scenarios involving surfaces to prevent objects from accelerating through them.
Review Questions
What formula is used to calculate the weight of an object?
Why does an object's weight change when it moves from Earth to another planet?
How does normal force relate to an object's weight when it is resting on a flat surface?
Related terms
Mass: A measure of the amount of matter in an object, typically measured in kilograms (kg), independent of gravity.
Gravitational Acceleration: The acceleration due to gravity experienced by an object, approximately $9.8 \frac{m}{s^2}$ near Earth's surface.
Normal Force: A support force exerted upon an object that is in contact with another stable object, acting perpendicular to the surface.