Let f be the force acting on a particle

Asked by admin @ 11/08/2021 in Physics viewed by 287 People

If F is the force acting on a particle having position vector r and T the torque of this force about the origin, then a. r.T=0 and F.T=0 b. r.T=0 and F.T≠0 c. r.T≠0 and F.T=0 d. r.T≠0 and F.T≠0 e. None of these

Answered by admin @ 11/08/2021

Torque is the cross product of Force Vector F and Position Vector r.

Thus T=r×F (vector form)

In a cross product, the resultant Vector (here T) is always perpendicular to both of the two vectors whose product is found.

So, here T is perpendicular to both Forward and r.

So, angle between T and F =90°
Similarly, angle between T and r=90°

Also for two vectors a and b, their dot product is

a.b = |a| |b| cos (theta) , where theta is angle between a and b

Following the two statements given above,

r.T = |r| |T| cos 90° = 0
F.T= |F| |T| cos 90° = 0

So, your answer is Option A,
r.T = 0 and F.T=0

A hair dryer with a resistance of 9.6 ohms operates at 120 volts for 2.5 minutes. the total electrical energy used by the dryer during this time interval is

Asked by maham237 @ 13/01/2021 in Physics viewed by 1204 persons

Mind map for light reflection and refraction class 10

Asked by admin @ 23/08/2021 in Physics viewed by 1146 persons

The african cicada is the world's loudest insect, producing a sound intensity level of 107 db at a distance of 0.50 m. what is the intensity of its sound (in w/m2) as heard by someone standing 3.1 m away? express your answer in watts per meter squared.

Asked by maham237 @ 10/01/2021 in Physics viewed by 1098 persons

A thief runs at a speed of 10m s

Asked by admin @ 23/08/2021 in Physics viewed by 1095 persons

A 5.8 x 10 4 watt elevator motor can lift

Asked by maham237 @ 20/06/2021 in Physics viewed by 1080 persons

Let f be the force acting on a particle

Similar Questions

A position dependent force f acting on a particle

If the buoyant force f acting on an object

A particle is acted upon by four forces simultaneously

Two forces acting on a particle in opposite directions

What minimum force f is needed to lift the piano

What happens when a net force acts on an object

A force of 7n acts on an object

A force of 7 n acts on an object

Force between two objects of equal masses is f

There are four forces acting at a point p

The work done by a force f 6x 3

A charged particle having charge q experience a force

What are the forces acting on an object at rest

Sum of all forces acting on an object is zero

The sum of all the forces acting on an object

Most viewed questions in Physics

Jeevandeep health and physical education std 10 answers pdf

Hc verma physics class 9 solutions of describing motion

How to leave nightmare land answer key

Base area and stability of some objects with different shapes

Which of the following statements about safe lifting are correct

Porous water-absorbing mass of fibers

Absorption of water by filter paper is due to

A composite wire of uniform diameter 3mm

At a distance l 400m from the traffic light

A rocket of mass m is launched straight up with thrust f⃗ thrust.

A hair dryer with a resistance of 9.6 ohms operates at 120 volts for 2.5 minutes. the total electrical energy used by the dryer during this time interval is

Mind map for light reflection and refraction class 10

The african cicada is the world's loudest insect, producing a sound intensity level of 107 db at a distance of 0.50 m. what is the intensity of its sound (in w/m2) as heard by someone standing 3.1 m away? express your answer in watts per meter squared.

A thief runs at a speed of 10m s

A 5.8 x 10 4 watt elevator motor can lift