Home
Class 12
PHYSICS
Consider a disc of mass m and radius R p...

Consider a disc of mass `m` and radius `R` placed on a rough plank of mass `M` which is turn is place on a smooth horizontal surface. Now plank is pulled by a force `F` and disc starts to roll on the plank.
If there is no friction any where then find
`(a)` Fricition force acting on the disc
`(b)` Angular acceleration of the disc

Text Solution

Verified by Experts

Let us apply Newton's laws on disc in horizontal direction

`f=ma`……..`(i)`
For plank
`F-f=Ma_(1)`……….`(ii)`
Applying torque equation on disc about centre of mass
`tau=l alpha`
`impliesfR=(mR^(2))/(2)alpha`........`(iii)`
For pure rolling
`a_(1)=a+Ralpha`.......`(iv)`
Solving the four equations, we get
`f=(Fm)/(m+3M)`, `alpha=(2F)/((m+3M)R)`
Promotional Banner

Topper's Solved these Questions

  • SYSTEM OF PARTICLES AND ROTATIONAL MOTION

    AAKASH INSTITUTE ENGLISH|Exercise Assignment (Section - A) Objective Type Questions (One option is correct)|62 Videos

  • SYSTEM OF PARTICLES AND ROTATIONAL MOTION

    AAKASH INSTITUTE ENGLISH|Exercise Assignment (Section - B) Objective Type Questions (One option is correct)|60 Videos

  • SYSTEM OF PARTICLES AND ROTATIONAL MOTION

    AAKASH INSTITUTE ENGLISH|Exercise Try Yourself|63 Videos

  • SEMICONDUCTOR ELECTRONICS: MATERIALS, DEVICES AND SIMPLE CIRCUITS

    AAKASH INSTITUTE ENGLISH|Exercise Assignment (Section-D (Assertion and reason))|5 Videos

  • TEST 1

    AAKASH INSTITUTE ENGLISH|Exercise EXERCISE|21 Videos

Similar Questions

Explore conceptually related problems

A sphere of mass m and radius r is placed on a rough plank of mass M . The system is placed on a smooth horizontal surface. A constant force F is applied on the plank such that the sphere rolls purely on the plank. Find the acceleration of the sphere.

A disc of mass m and radius R is placed over a plank of same mass m. There is sufficient friction between disc and plank to prevent slipping. A force F is applied at the centre of the disc. Force of friction between the disc and the plank is

A disc of mass m and radius R is placed over a plank of same mass m. There is sufficient friction between disc and plank to prevent slipping. A force F is applied at the centre of the disc. Acceleration of the plank is

A plank with a uniform sphere placed on it rests on a smooth horizontal plane. The plank is pulled to the right by a constant force F . It the sphere does not slip over the plank, then

A plank with a uniform sphere placed on it resting on a smooth horizontal plane. Plank is pulled to right by a constant force F . If sphere does not slip over the plank. Which of the following is incorrect?

A uniform disc of mass m , radius R is placed on a smooth horizontal surface. If we apply a horizontal force F at P as shown in the figure. If F = 4 N, m= .1 kg, R = 1 m and r = 1/2 m then, find the: angular acceleration of the disc. (rads^(-1))

A uniform disc of mass m and radius R is rolling up a rough inclined plane which makes an angle of 30^@ with the horizontal. If the coefficients of static and kinetic friction are each equal to mu and the only force acting are gravitational and frictional, then the magnitude of the frictional force acting on the disc is and its direction is .(write up or down) the inclined plane.

A disc and a solid sphere of same mass and radius roll down an inclined plane. The ratio of thhe friction force acting on the disc and sphere is

A uniform disc of mass m , radius R is placed on a smooth horizontal surface. If we apply a horizontal force F at P as shown in the figure. If F = 4 N, m= .1 kg, R = 1 m and r = 1/2 m then, find the: acceleration of the CM (in ms^(2) )

A man of mass m is standing on a plank of equal mass m resting on a smooth horizontal surface. The man starts moving on the plank with speed u relative to the plank. The speed of the man relative to the ground is