## A spring of spring constant 200 N/m has a block of mass 1 kg hanging at its one end and other end of spring…

Q: A spring of spring constant 200 N/m has a block of mass 1 kg hanging at its one end and other end of spring is attached to ceiling of an elevator. The elevator is rising upwards with an acceleration g/3. What should be the angular frequency and elongation during the time when the elevator is accelerating ?

Ans: (a)

## A particle executes SHM on a straight line. At two positions, its velocities are u and v while accelerations…

Q: A particle executes SHM on a straight line. At two positions, its velocities are u and v while accelerations are α  and β  respectively [β > α > 0]. The distance between these two positions is

(a) $\displaystyle \frac{u^2 + v^2}{\alpha + \beta}$

(b) $\displaystyle \frac{u^2 - v^2}{\alpha + \beta}$

(c) $\displaystyle \frac{u^2 - v^2}{\beta - \alpha }$

(d) $\displaystyle \frac{u^2 + v^2}{\beta - \alpha }$

Ans: (b)

## A particle executes SHM with a time period of 16 s. At time t = 2s, the particle crosses the mean position…

Q: A particle executes SHM with a time period of 16 s. At time t = 2s, the particle crosses the mean position while at t = 4s, its velocity is 4ms-1. The amplitude of motion in metre is

(a) √2 π

(b) 16√2 π

(c) 32√2 π

(d) 4/π

Ans: (c)

## The period of a particle in SHM is 8s. At t = 0, it is at the mean position. The ratio of the distances…

Q: The period of a particle in SHM is 8s. At t = 0, it is at the mean position. The ratio of the distances travelled by it in the 1st and the 2nd second is

(a) 1/2

(b) 1/√2

(c) √2

(d) √2+1

Ans: (d)

## The amplitude of a damped oscillator becomes 1/27 th of its initial value after 6 minutes….

Q: The amplitude of a damped oscillator becomes 1/27 th of its initial value after 6 minutes. Its amplitude after 2 minutes is

(a) A0/3

(b) A0/9

(c) A0/54

(d) A0/81

Ans: (a)