Consider a block kept on an inclined plane (inclined at $45^{\circ}$ ) as shown in the figure. If the force required to just push it up the incline is $2$ times the force required to just prevent it from sliding down, the coefficient of friction between the block and inclined plane $(\mu)$ is equal to
JEE MAIN 2023, Difficult
Download our app for free and get startedPlay store
$F _1= mg \sin 45^{\circ}+ f = mg \sin 45^{\circ}+\mu N$

$F _1=\frac{ mg }{\sqrt{2}}+\mu mg \cos 45^{\circ}$

$F _1=\frac{ mg }{\sqrt{2}}(1+\mu)$

$F _2= mg \sin 45^{\circ}- f = mg \sin 45^{\circ}-\mu N$

$=\frac{ mg }{\sqrt{2}}(1-\mu)$

$F _1=2 F _2$

$\frac{ mg }{\sqrt{2}}(1+\mu)=2 \frac{ mg }{\sqrt{2}}(1-\mu)$

$1+\mu=2-2 \mu$

$\mu=1 / 3=0.33$

art

Download our app
and get started for free

Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*

Similar Questions

  • 1
    In the given arrangement of a doubly inclined plane two blocks of masses $\mathrm{M}$ and $\mathrm{m}$ are placed. The blocks are connected by a light string passing over an ideal pulley as shown. The coefficient of friction between the surface of the plane and the blocks is $0.25$ . The value of $\mathrm{m}$, for which $\mathrm{M}=10$ $\mathrm{kg}$ will move down with an acceleration of $2 \mathrm{~m} / \mathrm{s}^2$, is : (take $\mathrm{g}=10 \mathrm{~m} / \mathrm{s}^2$ and $\left.\tan 37^{\circ}=3 / 4\right)$
    View Solution
  • 2
    A roller coaster is designed such that riders experience "weightlessness" as they go round the top of a hill whose radius of curvature is $20\, m.$ The speed of the car at the top of the hill is between
    View Solution
  • 3
    A small body slips, subject to the force of friction, from point $A$ to point $B$ along two curved surfaces of equal radius, first along route $1,$ then along route $2$. Friction does not depend on the speed and the coefficient of friction on both routes is the same. In which case will the body’s speed at $B$ be greater?
    View Solution
  • 4
    Starting from rest a body slides down a $45^o$ inclined plane in twice the time it takes to slide down the same distance in the absence of friction. The co-efficient of friction between the body and the inclined plane is: 
    View Solution
  • 5
    A car of weight $W$ is on an inclined road that rises by $100\,m$ over a distance of $1\,Km$ and applies a constant frictional force $\frac {W}{20}$ on the car. While moving uphill on the road at a speed of  $10\,ms^{-1},$ the car needs power $P.$  If it needs power $\frac {P}{2}$ while moving down hill at speed $v$ then value of $v$ is ........ $ms^{-1}$
    View Solution
  • 6
    The upper half of an inclined plane of inclination $\theta$ is perfectly smooth while the lower half is rough. A body starting from the rest at top comes back to rest at the bottom if the coefficient of friction for the lower half is given by
    View Solution
  • 7
    A block pressed against the vertical wall is in equilibrium. The minimum coefficient of  friction is:-
    View Solution
  • 8
    A uniform rod of length $l$ is being rotated in a horizontal plane with a constant angular speed about an axis passing through one of its ends. If the tension generated in the rod due to rotation is $T(x)$ at a distance $x$ from the axis, then which of the following graphs depicts it most closely?
    View Solution
  • 9
    A block of mass $2 \,kg$ rests on a rough inclined plane making an angle of $30°$ with the horizontal. The coefficient of static friction between the block and the plane is $ 0.7$. The frictional force on the block is ....... $N$.
    View Solution
  • 10
    A metal block is resting on a rough wooden surface. A horizontal force applied to the block is increased uniformly. Which of the following curves correctly represents  velocity of the block ? 
    View Solution