SHMMedium

Question

A disc of mass 3 m and a disc of mass m are connected by massless spring of stiffness k. The heavier disc is placed in on the ground with spring vertical and lighter disc on top. From its equilibrum position, the upper disc is pushed down by a distance δ and released. Then

Options

A.if δ > 3mg /k, the lower disc will bounce up
B.if δ = 2 mg /k, maximum normal reaction from ground on lower disc = 6 mg
C.if δ = 2 mg /k, maximum normal reaction from ground on lower disc = 4 mg
D.if δ = 2 mg /k, the lower disc will bounce up

Solution

From energy conservation

At equilibrium position                 To leave surface
    mg = kx0                                      kx1 = 3mg
kδ12 = mg (δ1 + x1) + kx12
⇒δ12 - = 0
⇒ δ1
⇒ If δ > the lower disk will bounce up.
Now If δ = then maximum normal reaction from ground on lower disk
N = 3mg + k(x0 + δ) = 6mg

Create a free account to view solution

View Solution Free
Topic: SHM·Practice all SHM questions

More SHM Questions

Savitha, a XI standard student, while conducting an experiment to determine the effective length of a simple pendulum $L...A test tube of length l and area of cross-section A has some iron fillings of mass M as shown in figure. The test tube f...A string OP of length L is fixed at both ends and vibrates in its first overtone with time period T and maximum amplitud...A rod of length L is suspended from its one end and is oscillating. Its time period will be :...If the mass of the bob in a simple pendulum is increased to thrice its original mass and its length is made half its ori...