# Why an ice skater is able to increase her angular velocity by folding her arms?

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## Why an ice skater is able to increase her angular velocity by folding her arms?

When the hands and legs are brought close to the rotational axis, the rotational inertia decreases thereby increasing the skaters angular velocity as per the conservation of angular momentum. Increase in angular velocity implies increase in the kinetic energy.

## Why do ice skaters spin faster when they pull their arms in physics?

The conservation of angular momentum explains why ice skaters start to spin faster when they suddenly draw their arms inward, or why divers or gymnasts who decrease their moment of inertia by going into the tuck position start to flip or twist at a faster rate.

## Why is it harder for an ice skater to spin with his arms stuck out as opposed to tucked in?

A figure skater spins, with her arms outstretched, with angular velocity of ωi. When she moves her arms close to her body, she spins faster. Her moment of inertia decreases, so her angular velocity must increase to keep the angular momentum constant.

## How skaters can change angular velocity without applying extra force?

By pulling in her arms, the skater decreases her moment of inertia (all her mass is closer to the middle), so her angular velocity has to increase in order to keep her angular momentum constant.

## When an ice skater spins and increases her rotation rate by pulling her arms and leg in what happens to her rotational kinetic energy?

Her angular momentum is conserved because the net torque on her is negligibly small. In the next image, her rate of spin increases greatly when she pulls in her arms, decreasing her moment of inertia. The work she does to pull in her arms results in an increase in rotational kinetic energy.

## Why does a figure skater spin faster when she has her arms closer to her chest and spin slower when she has her arms stretched outwards?

The principle of the conservation of angular momentum holds that an object’s angular momentum will stay the same unless acted upon by an outside force. This explains why a figure skater spins faster when she tucks her arms in close to her body.

## Why an ice skater stretches out arms and legs during performance?

During the course of their performance, an ice skater, a ballet dance or an acrobat take angular of the principle of conservation of angular momentum (i.e Iω= constant), by stretching out arms and legs or vice-versa. On doing so, their moment of inertia increases/decreases.

## Why does she speed up when her arms are brought closer to her body?

The principle of the conservation of angular momentum holds that an object’s angular momentum will stay the same unless acted upon by an outside force. This explains why a figure skater spins faster when she tucks her arms in close to her body.

## Why a dancer spins faster when her arms are folded due to?

This is due to. constant angular momentum and increase in KE.

## How do skaters spin so fast?

## When a spinning figure skater pulls?

After a few rotations, the skater pulls both arm in closer to the body and spins faster. In physics, we call this conservation of angular momentum. Just as an example, here is this same maneuver performed on a rotating platform instead of on ice.

## How can I spin faster in the air?

## Why an ice skater or a ballet dancer can increase her angular velocity by folding her arms and bringing the stretched leg close to the other leg?

When she folded her hands and brings the stretched legs close to the other leg, her moment of inertia decreases and hence her angular speed increases.

## When a spinning skater pulls in her arms she increases her angular momentum?

This is the result of conservation of angular momentum. As the skater reduces her moment of inertia by pulling her arms and legs in, closer to the axis of rotation, her angular speed increases to order to maintain constant angular momentum.

## How are figure skaters able to increase the angular velocity of a spin without additional input of energy?

Given that no outside force is applied, the angular momentum is conserved. When the skater extends her arms or legs, she effectively increases her radius, and thus changes her moment of inertia. Since the angular momentum remains constant, what changes is the angular velocity of the spin.

## What happens to her angular speed when she pulls her arms in?

When she pulls her arms in, her rotational inertia is reduced. Since there is no external net torque on the ice skater, her angular momentum remains constant because her angular velocity magnitude increases.