When a high diver in a swimming event springs from the board and “tucks in”, a rapid spin **result**. Why is this?

Answer: This is the consequence of **conservation** of **angular** momentum.

The **angular** momentum of a **body** is the **product** of Moment of inertia (*A measure of rotational inertia and it depends on the mass as well as distribution of mass about the axis of rotation. Farther the masses, greater will be the rotational inertia*) and the

**angular**

**velocity**(The speed of

**rotation**)

The **angular** momentum of a **body** remains unchanged in the **absence** of any external torque.

When the diver dives, he is giving his **body** a turning and takes off with his limbs stretched. In the stretched **position**, the **moment of inertia** is more. When he “tucks in”, the **moment of inertia** decreases. But since this happens without any external torque, it would **result** in an increase in **angular** **velocity** so as to keep the **angular** momentum constant.