weight

(noun)

The force on an object due to the gravitational attraction between it and the Earth (or whatever astronomical object it is primarily influenced by).

Related Terms

Examples of weight in the following topics:

  • Weight

    • In physics, it is important to differentiate the weight of an object from its mass.
    • On the other hand, the weight of an object is an extrinsic quantity.
    • In US customary units, the weight of an object can be expressed in pounds.
    • In this case, the weight of the object varies due to the force of buoyancy.
    • A spring scale measures weight by finding the extent to which a spring is compressed.This is proportional to the force that a mass exerts on the scale due to its weight.

  • Mass

    • At its 2011 meeting, the General Conference on Weights and Measures (CGPM) agreed that the kilogram should be redefined in terms of the Planck constant.
    • In everyday usage, the mass of an object in kilograms is often referred to as its weight.
    • In scientific terms, 'weight' refers to the gravitational force acting on a given body.
    • For example, a person's weight on the Earth is different than a person's weight on the moon because of the differences in the gravitational pull of each body.
    • Accordingly, astronauts in microgravity must exert 10 times more force to accelerate a 10-kg object at the same rate as a 1-kg object, even though the differences in weight are imperceptible.

  • Flotation

    • So, for a floating object on a liquid, the weight of the displaced liquid is the weight of the object.
    • When any boat displaces a weight of water equal to its own weight, it floats.
    • This is often called the "principle of flotation" where a floating object displaces a weight of fluid equal to its own weight.
    • Every ship, submarine, and dirigible must be designed to displace a weight of fluid equal to its own weight.
    • The buoyant force, which equals the weight of the fluid displaced, is thus greater than the weight of the object.

  • Normal Forces

    • Bob has a weight of 800 N.
    • Because of Newton's third law, the ground exerts a force on the person that is equal in magnitude to the person's weight.
    • In this simple case, the weight of the person and the opposing normal force are the only two forces considered on the person.
    • The person remains still because the forces due to weight and the normal force create a net force of zero on the person.
    • In this case, the normal force is not in the exact opposite direction as the force due to the weight of the mass.

  • Buoyancy and Archimedes' Principle

    • If the buoyant force is greater than the object's weight, the object will rise to the surface and float.
    • If the buoyant force is less than the object's weight, the object will sink.
    • If the buoyant force equals the object's weight, the object will remain suspended at that depth.
    • However, we also know that the buoyancy force on the fluid must be equal to its weight, as the fluid does not sink in itself.
    • The buoyant force on the ship (a) is equal to the weight of the water displaced by the ship—shown as the dashed region in (b).

  • Mass

    • The terms mass and weight are often interchanged, however it is incorrect to do so.
    • Weight is a different property of matter that, while related to mass, is not mass, but rather the amount of gravitational force acting on a given body of matter.

  • Locating the Center of Mass

    • The position of COM is mass weighted average of the positions of particles.
    • This mean means that position of COM is mass weighted average of the positions of particles.
    • In three dimensions: By supporting an object at three points and measuring the forces that resist the weight of the object, COM of the three-dimensional coordinates of the center of mass can be determined.

  • Translational Equilibrium

    • A book resting on a table is pushing down on the table with the force of its weight .
    • Notice that the amount of force that the table is pushing upward on the object (the N vector) is equal to the downward force of the object's weight (shown here as mg, as weight is equal to the object's mass multiplied by the acceleration due to gravity): because these forces are equal, the object is in a state of equilibrium (all the forces acting on it balance to zero).

  • Free-Falling Objects

    • Free fall is the motion of a body where its weight is the only force acting on an object.
    • Free fall is the motion of a body where its weight is the only force acting on an object.

  • Dosimetry

    • The weighting factor (wr) and tissue/organ weighting factor (WT) have been established.
    • The weighting factor for the whole body is 1, such that 1 Gy of radiation delivered to the whole body is equal to one sievert.