Question
Physics Question on projectile motion
A body of mass 'm' is projected with a speed 'u' making an angle of 45∘ with the ground. The angular momentum of the body about the point of projection, at the highest point, is expressed as Xg2mu3. The value of 'X' is ______.
Answer
At the highest point, the vertical component of the velocity becomes zero, and only the horizontal component ux=ucos45∘=2u remains.
The maximum height h reached by the body is given by:
h=2g(usin45∘)2=2g(2u)2=4gu2.
The angular momentum L about the point of projection at the highest point is:
L=m⋅ux⋅h=m⋅2u⋅4gu2=8g2mu3.
Thus, the value of X is:
X=8.