FrictionHard
Question
In the given figure the coefficient of friction between 4kg and 5 kg blocks is 0.2 and between 5 kg block and ground is 0.1 respectively. Choose the correct statements
Options
A.Minimum force needed to cause system to move is 17 N
B.When force is 4N static friction at all surfaces is 4N to keep system at rest
C.Maximum acceleration of 4kg block is 2m/s2
D.Slipping between 4kg and 5 kg blocks start when F is > 17N
Solution
So block ′Q′ is moving due to force while block ′P′ due to friction.
Friction direction on both +Q blocks as shown.
First block ′Q′ will move and P will move with ′Q′ so by FBD taking ′P′ and ′Q′ as system
F − 9 = 0 ⇒ F = 9 N
When applied force is 4 N then FBD
4 kg block is moving due to friction and maximum friction force is 8 N.
So acceleration = 8/4 = 2/m/s2 - amax.
Slipping will start at when Q has +ve acceleration equal to maximum acceleration of P i.e. 2 m/s2.
F − 17 = 5 × 2 ⇒ F = 27 N.
Friction direction on both +Q blocks as shown.
First block ′Q′ will move and P will move with ′Q′ so by FBD taking ′P′ and ′Q′ as system
F − 9 = 0 ⇒ F = 9 N
When applied force is 4 N then FBD
4 kg block is moving due to friction and maximum friction force is 8 N.
So acceleration = 8/4 = 2/m/s2 - amax.
Slipping will start at when Q has +ve acceleration equal to maximum acceleration of P i.e. 2 m/s2.
F − 17 = 5 × 2 ⇒ F = 27 N.
Create a free account to view solution
View Solution FreeMore Friction Questions
With what minimum velocity should block be projected along belt from left end A towards end B such that it reaches the e...Figure shows a block kept on a rough inclined plane. The maximum external force down the incline for which the block rem...The coefficient of friction between the block and the horizontal surface is μ as shown in figure. The block moves t...A uniform chain has mass M and length L. If is placed on a frictionless table with length l0 hanging over the edge. The ...Block of mass m is on an inclined plane of angle θ. The coefficient of friction between the block and the plane is ...