Physics Doubt

If an insect inside a light, hollow ball moves inside it, the ball moves, thus the position of centre of mass of the ball changes. According to Newton's laws of motion, as long as no external force is applied to a body the centre of mass remains at rest. Then how this internal force changes the position of centre of mass of the body?

#Mechanics

Easy Math Editor

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Comments

Because of gravity and friction, there's an external reaction force from the ground when the insect walks inside the ball. It's not any different from an insect walking directly on the ground.

To illustrate this point, let's imagine putting the light hollow ball on water so that it floats. As the insect walks inside the ball, what happens?

Michael Mendrin - 5 years, 5 months ago

Because newtorns law is applicabe to point objects .

A Former Brilliant Member - 4 years, 11 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$