Weight of a body of mass m in its fall above the surface of the earth is
- mg
- √mg
- infinity
- m√g
- zero
The Correct Option is
Approach Solution - 1
Weight is the force exerted by gravity on an object. The weight of a body is given by the formula: \[ W = mg \] where \( m \) is the mass of the object and \( g \) is the acceleration due to gravity. However, when a body is in free fall, it experiences a state of weightlessness. This is because the force of gravity acting on the body and the acceleration due to gravity are balanced, resulting in no normal force acting on the body.
Therefore, the effective weight of the body is zero while in free fall.
The correct option is (E) : zero
Approach Solution -2
Answer: mg
Explanation:
The weight of a body is defined as the force with which it is attracted towards the Earth due to gravity. It is given by the formula: $$ W = mg $$ where:
- $W$ is the weight of the body
- $m$ is the mass of the body
- $g$ is the acceleration due to gravity (approximately \(9.8 \, \text{m/s}^2\) near the Earth's surface)
Even during free fall (neglecting air resistance), the weight remains mg. What changes is the apparent weight if the body is in a reference frame that's also falling.
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