Home
Class 12
PHYSICS
Average torque on a projectile of mass m...

Average torque on a projectile of mass `m` (initial speed `u` and angle of projection `theta`) between initial and final positions `P` and `Q` as shown in figure, about the point of projection is :
.

A

`(mu^(2) sin 2theta)/2`

B

`m u^(2) cos theta`

C

`m u^(2) sin theta`

D

`(m u^(2) cos theta)/2`

Text Solution

Verified by Experts

The correct Answer is:
A
`tau_(av).Deltavect = DeltaL` Here, `Deltat`= time of flight `=(2mu sin theta)/g`……….(1)
`|DeltavecL| =|(vecL_(f) - vecL_(j))|` about point of projection.
`=(mu sin theta)("range") -0 =((m u sintheta)(mu^(2) sin 2theta))/g`
`(mu u^(2) sintheta 2theta)/g therefore |vectau_(av)| =(vecDeltaL)/(Deltat) = (mu^(3) sin theta sin 2theta)/g .g/(2u sin theta) = (m u^(2) sin 2theta)/2`
Promotional Banner

Similar Questions

Explore conceptually related problems

A stone is projected with speed u and angle of projection is theta . Find radius of curvature at t=0.

If a projectile has a constant initial speed and angle of projection, find the relation between the chages in the horizontal range due to change in accelertion due to grvity.

A particle of mass m is projected with a speed v_(0) at an angle of projection theta with horizontal. Find the torque of the weight of the particle about the point of projection after time (v_(0)sintheta)/(g)

The speed of a projectile at its maximum height is half of its initial speed. The angle of projection is .

A particle of mass m is thrown with speed u at an angle of projection theta with horizontal. The average power imparted by the gravitational force until it strikes the ground is

A particle of mass m is projected with an initial velocity U at an angle theta to the horizontal. The torque of gravity on projectile at maximum height about the point of projection is

Two particles A and B are projected in same vertical plane as shown in figure.Their initial positions (t=0) , initial spped and angle of projections are indicated in the diagram.If initial angle of projection theta_(B)=37^(@) , what should be initial speed of projection of particle B , so that it hits particle A . U_(A)=60m//s

A particle of mass m is projected with a speed u at an angle theta with the horizontal. Find angular momentum of particle after time t about point of projection.

A particle of mass m is projected from the ground with an initial speed u at an angle alpha . Find the magnitude of its angular momentum at the highest point of its trajector about the point of projection.

A projectile thrown with an initial speed u and the angle of projection 15^@ to the horizontal has a range R . If the same projectile is thrown at an angle of 45^@ to the horizontal with speed 2 u , what will be its range ?