Home
Class 11
PHYSICS
A force F=2t is spplied at t=0 sec to th...


A force `F=2t` is spplied at `t=0` sec to the block of mass m placed on a rough horizontal surface. The coefficient of static and kinetic friction between the block and surface are `mu_S` and `mu_k` rspectively. Which of the following graphs best represents the acceleration vs time of the block`(mu_Sgtmu_k)`?

A

B

C

D

Text Solution

Verified by Experts

The correct Answer is:
D
Let `t_(0)` be the time when friction force is maximum
`F=2t_(0)=mu_(g)mg`
The block just starts moving immediately after this instant, with acceleration
`=(mu_(s)mg-mu_(k)mg)/(m)=(mu_(s)-mu_(k))g`
For `tgtt_(0)` the acceleration of the block is
`a=(2t_(0)-mu_(k)mg)/(m)`
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • DAILY PRACTICE PROBLEMS

    RESONANCE|Exercise Comprehension|127 Videos

  • DAILY PRACTICE PROBLEMS

    RESONANCE|Exercise dpp 31|7 Videos

  • DAILY PRACTICE PROBLEMS

    RESONANCE|Exercise dpp29|5 Videos

  • CURRENT ELECTRICITY

    RESONANCE|Exercise Exercise|54 Videos

  • ELASTICITY AND VISCOCITY

    RESONANCE|Exercise Advanced Level Problems|9 Videos

Similar Questions

Explore conceptually related problems

A block of mass 2kg is resting on a rough horizontal surface.The coefficients of static and kinetic frictions between the block and surface are 0.7 and 0.6 respectively.A horizontal force F=(4N/s)times t is applied on the block at t=0.At t=4s ,the force of friction on the block is (take g=10m/s^(2) )

Coefficient of kinetic friction and coefficient of static friction between two blocks is mu_(k) and mu_(s) respectively. In general

Knowledge Check

  • A block of mass M is using on a rough horizontal surface. mu_R is the coefficient of kinetic friction between the block and the surface. What is the net force exerted by the surface on the block?

    A
    Mg
    B
    `muMg`
    C
    `Mgsqrt(1+mu_(K)^(2))`
    D
    `Mgsqrt(1-mu_(K)^(2))`

  • A block of mass m lying on a rough horizontal surface of friction coefficient mu is pulled by a force F as shown , the limiting friction between the block and surface will be

    A
    `mu mg`
    B
    `mu(mg + (F)/(2))`
    C
    `mu(mg - (F)/(2))`
    D
    `mu(mg - (sqrt(3) F)/(2))`

  • A block of mass 3kg is placed on a rough horizontal surface (mu_(s)=0.4) . A forc eof 8.7N is applied on th eblock. The force of friction between the block and floor is .

    A
    `8.7N`
    B
    12N
    C
    10N
    D
    zero

    • Similar Questions

    Explore conceptually related problems

    A block of mass M is kept on as rough horizontal surface. The coefficient of static frictionbetween the block and the surface is mu . The block is to be pulled by applying a force to it. What minimum force is needed to slide the block? In which direction should this force act?

    A block of mass 1 kg lies on a horizontal surface in a truck. The coefficient of static friction between the block and the surface is 0.6. If the acceleration of the truck is 5m//s^2 , the frictional force acting on the block is…………newtons.

    A block of mass m is pulled by a force of constant power P placed on a rough horizontal plane. The friction coefficient between the block and the surface is mu . Then

    A block of mass 5kg is lying on a rough horizontal surface. The coefficient of static and kinetic friction are 0.3 and 0.1 and 10m//s^(-2) . If a horizontal force of 50N is applied on the block, the frictional force is

    A block of mass m is placed on a rough horizontal surface. If minimum force to pull the block is (mg)/(2) then coefficient of friction is :

    Home
    Profile