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
A solid hemisphere of weight P rests with its curved surface in contact with a rough inclined plane. A weight Q is place...The time taken by a body to slide down a rough 45o inclined plane is twice that required to slidedown a smooth 45° incli...A block of mass m is placed on a surface with a vertical cross-section given by y =. If the coefficient of friction is 0...A system is shown in the figure, which is released from rest. There is no friction between ground and mass 5m. The coeff...Two persons, pull each other through a massless rope in ′tug of war′ game. Who will win ?...