Question

Relation between Angular Momentum and Torque.

Answer 1

ΣF = dp/dt.

where ΣF is the net force acting on a body.  Thus we can write

r ´ ΣF = r ´ dp/dt.

Since the net torque acting on a body is Στ = r ´ ΣF, and since we can add to the right hand side of the preceding equation the quantity dr/dt ´ p = 0 without changing its value, we can write

Στ = r ´ dp/dt + dr/dt ´ p = d(r ´ p)/dt.

We define angular momentum as

 L º r ´ p

The preceding equation then becomes

Σ= d L/dt,

Answer 2

torque= angular momentum/time