## Moment Of Inertia:

When an object is at rest, it has higher inertia. It is tough to put it in a rotational motion. It is also tough to stop an object from its rotational motion when it has higher inertia.

## Shape Of A Semicircle:

It is a geometric shape that forms half a circle in its dimension. The area of a semicircle is valued at half the area of a full circle.

## Moment Of Inertia Of A Semicircle:

The formula for calculating the area moment of inertia of a semicircle is I = πr4 / 4. To find the moment of inertia of a semicircle, the moment of inertia of a full circle is calculated first. The result is then divided by half to derive the area moment of inertia of a semicircle.

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## Calculation:

To calculate the moment of inertia of a full circle, the x-axis relative is equal to the y axis relative. This is because of the symmetrical shape of the circle.

Moment of inertia of the circle:

## Centroid:

The point which lies at the exact centre of a shape is known as its centroid. Objects with uniform density have their centre of mass at their centroid. This indicates that at the point of centroid, the object will balance with as much mass on any side.

## The Centroid of a semicircle:

The centroid is the point where all the weight of an object or figure can be put at.

The centroid of a semicircle is located at 42.44 % of the radius along the y axis.

A Moment of inertia and centroid of a semicircle can help us donate the point which can carry the maximum weight of an object.

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## Derivation:

Moment of inertia on x axis is calculated as-

## Increase In The Moment Of Inertia Of A Body:

The Moment of inertia is the force that is required to rotate an object. It can be increased or decreased by increasing the distance of radius from the point of rotation. When there is an increase in the moment of inertia, the speed of rotation decreases. Similarly, a decrease in the moment of inertia leads to an increase in the speed of rotation of the object.

Factors Influencing Moment Of Inertia And Centroid Of A Convex Semicircle:

To find out the moment of inertia of any object or shape, it is important to determine the mass of the object first. After determining the mass of the object, it is important to derive the distance of the mass or radius of the distance from the point of rotation.

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## Significance Of Area Moment Of Inertia Of A Semicircle:

The Moment of inertia determines the possibility of rotation of an object. It is calculated using the mass of an object. It is an important concept of physics that is studied to figure out how the rotational ability of an object is affected when there is a change in the mass of the object.

The Moment of inertia and centroid of a semicircle is minimum at the centre of the body, as the mass is minimum. When the area moment of inertia of a semicircle is calculated through another axis and a distance of radius, it increases in value.

## Radius Of Gyration:

This parameter is used to determine the moment of inertia of a body by multiplying the square of distance with the mass of the body.

## Area Density:

Area Density is calculated by dividing mass by area. It is not calculated using the weight of the object, rather it is dependent on the uniformity of the mass of the object.

The Formula for calculating Area Density:

dm/da= σ

## Conclusion:

Area moment of inertia of a semicircle is the amount of force that is required to move the body rotationally on its axis. If the body has a larger moment of inertia, it would be harder to move. An Increase in moment of inertia can also make it harder to stop the rotational movement of an object. It is calculated using the mass of a body and the distance of radius from the axis of rotation. It helps us realise how there is a change in the rotational motion of an object when there is a change in its mass.