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 smooth block is released at rest on a 45o incline and then slides a distance d. The time taken to slide is n times as ...The coefficient of friction between the block and plank is μ and ground is smooth. The value of µ is such that block bec...In the arrangement shown in the figure mass of the block B and A are 2 m,, 8 m respectively. Surface between B and floor...The upper portion of an inclined plane of inclination a is smooth and the lower portion is rough. A particle slides down...Figure shows a block kept on a rough inclined plane. The maximum external force down the incline for which the block rem...