Apparent weight

Apparent weight is a concept in physics that refers to the weight an object appears to have when observed within a non-inertial frame of reference. This is different from the object's true weight, which is the force exerted by gravity on the object.

Definition

The apparent weight of an object is the force experienced by the support that holds it. When an object is in free-fall, its apparent weight is zero, even though its true weight remains constant. This is because the support force is zero.

Factors affecting apparent weight

Several factors can affect the apparent weight of an object. These include:

• Gravitational force: The force of gravity acting on an object is its true weight. However, the apparent weight can be different due to other forces acting on the object.

• Accelerative forces: If an object is accelerating upwards, its apparent weight is greater than its true weight. Conversely, if it is accelerating downwards, its apparent weight is less than its true weight.

• Buoyant forces: In a fluid, an object's apparent weight is less than its true weight due to the buoyant force acting on it.

Apparent weight in an elevator

A common example of apparent weight is the feeling of weightlessness or heaviness experienced in an elevator. When the elevator accelerates upwards, a person inside feels heavier because their apparent weight is greater than their true weight. When the elevator accelerates downwards, the person feels lighter because their apparent weight is less than their true weight.

Apparent weight in water

Another example of apparent weight is the feeling of weightlessness experienced when submerged in water. This is due to the buoyant force acting on the person, which reduces their apparent weight.

See also

• Weight
• Gravity
• Buoyancy
• Acceleration