Laws of MotionMedium
Question
Two block of mass m1 and m2 are connected with a mass less spring and placed over a plank moving with an acceleration ′a′ as show in figure. The coefficient of friction between the blocks and platform is μ.


Options
A.spring will be stretched if a > μg
B.spring will be compressed if a ≤ μg
C.spring will neither be compressed nor be stretched for a ≤ μg
D.spring will be in its natural lenght under all conditions
Solution
Let a ≤ μg (i.e. friction is static)
Then both the blocks are rest w.r.t plank
Therefore spring will be in its natural length.
Now let a > μg (i.e. friction is kinetic)
Then both the blocks are moving with same acceleration w.r.t plank.
In this case spring force is equal to zero
Then both the blocks are rest w.r.t plank
Therefore spring will be in its natural length.
Now let a > μg (i.e. friction is kinetic)
Then both the blocks are moving with same acceleration w.r.t plank.
In this case spring force is equal to zero
Create a free account to view solution
View Solution FreeMore Laws of Motion Questions
A boy sitting on the top most berth in the compartment of a train which is just going to stop on a railway station, drop...In the arrangement shown in fig. the ends P and Q of an unstretchable string move downwards with uniform speed U. Pulley...A lift is desending with an acceleration 2 m/sec2. What will be the aparent weight of a person of 80 kg mass ?...Which figure represents the correct F.B.D. of rod of mass m as shown in figure :...Figure shows the displacement of a particle going along the x-axis as a function of time :...