Home
Class 11
PHYSICS
A block of mass 1kg is at rest on a hori...

A block of mass 1kg is at rest on a horizontal table. The coeficient of static friction between the block and the table is `0.5` . The magnitude of the force acting upward at an angle of `60^(@)` from the horizontal that will just start the block moving is.

A

5 N

B

5.36 N

C

74.6 N

D

10 N

Text Solution

Verified by Experts

The correct Answer is:
B

From the figure, R+F `sin60^(@)=mg`
`:." "R=mg-Fsin60^(@)=mg-(sqrt3)/(2)F`
When the block just starts moving. The limiting force of friction, `f=muR`
and f=applied force=`Fcos60^(@)`
`:." "Fcos60^(@)=mu[mg-(sqrt3)/(2)F]`
`:." " F/2=1/2[1xx10-(sqrt3)/(2)F]`
`:." "F=10-(sqrt3)/(2)F`
`:." "F+(sqrt3)/(2)F=10" ":." "2F+sqrt3F=20`
`:." "F=(20)/(2+sqrt3)=(20)/(2+1.732)=(20)/(3.732)`
`:." "F=5.36 N`
Promotional Banner

Topper's Solved these Questions

  • FRICTIONAL IN SOLIDS AND LIQUIDS

    MARVEL PUBLICATION|Exercise TEST YOUR GRASP|10 Videos

  • FORCE, WORK AND TORQUE

    MARVEL PUBLICATION|Exercise TEST YOUR GRASP|10 Videos

  • MAGNETIC EFFECT OF ELECTRIC CURRENT

    MARVEL PUBLICATION|Exercise TEST YOUR GRASP|10 Videos

Similar Questions

Explore conceptually related problems

A block weighing 10kg is at rest on a horizontal table. The coefficient of static friction between the block and the table is 0.5 . If a force acts downward at 60^(@) with the horizontal, how large can it be without causing the block to move ? . (g =100ms^(-2)) .

A block on table shown in is just on the edge of slipping Find the coefficient of static friction between the blocks and table .

A block of mass 0.1 is held against a wall applying a horizontal force of 5N on block. If the coefficient of friction between the block and the wall is 0.5, the magnitude of the frictional force acting on the block is:

In Fig. 6-37, a block of mass m = 5.0 kg is at rest on a ramp. The coefficient of static friction between the block and ramp is not known. Find the magnitude of the net force exerted by the ramp on the block.

A block of mass 1kg lies on a horizontal surface in a turck, the coefficient of static fricition between the block and the surface is 0.6, what is the force of fricition on the block. If the acceleration of the truck is 5m//s^(2) .

A block of mass 1kg is pressed against a wall by applying a horizontal force of 10N on the block. If the coefficient of friction between the block and the wall is 0.5 ,magnitude of the frictional force acting on the block is

A block of mass 0.1 kg is held against a wall by applying a horizontal force of 5 N on the block. If the coefficient of friction between the block and the wall is 0.5, then the magnitude of the frictional force acting on the block is

A block of mass 1 kg is placed on a truck which accelerates with acceleration 5ms^(-2) . The coefficient of static friction between the block and truck is 0.6. The frictional force acting on the block is