JEE Physics

StemEZ

Chapter 23

Experiment - Simple Pendulum - all with Video Answers

Educators

Chapter Questions

Problem 2781

Complete the following sentence. Time period of oscillation of a simple pendulum is dependent on.........
(A) Length of thread
(B) initial phase
(C) amplitude
(D) mass of bob

Narayan Hari

Narayan Hari

Numerade Educator

Problem 2782

Complete the following sentence. In a damped oscillation of
a pendulum.........
(A) the sum of potential energy and kinetic energy is conserved.
(B) mechanical energy is not conserved
(C) the kinetic energy is conserved
(D) the potential energy is conserved

Narayan Hari

Numerade Educator

Problem 2783

If the time period of undamped oscillation is $\mathrm{T}$ and that of damped oscillation is $\mathrm{T}^{\prime}$, then what is the relation between $\mathrm{T} \& \mathrm{~T}^{\prime}$
(A) $\mathrm{T}^{\prime}<\mathrm{T}$
(B) nothing can be said, unless the drag force constant is known.
(C) $\mathrm{T}^{\prime}=\mathrm{T}$
(D) $\mathrm{T}^{\prime}>\mathrm{T}$

Narayan Hari

Numerade Educator

Problem 2784

The energy dissipated in a damped oscillation..........
(A) decays exponentially
(B) decay curve will depend on the drag constant
(C) decays linearly
(D) decays following a sine curve with diminishing amplitude.

Narayan Hari

Numerade Educator

Problem 2785

What is the equation for a damped oscillator, where $\mathrm{k}$ and $\mathrm{b}$ are constants and $\mathrm{x}$ is displacement.
(A) $\left\{\left(\mathrm{md}^{2} \mathrm{x}\right) /\left(\mathrm{dt}^{2}\right)\right\}+\mathrm{kx}+\{(\mathrm{dbx}) /(\mathrm{dt})\}=0$
(B) $\left\{\left(\mathrm{md}^{2} \mathrm{x}\right) /\left(\mathrm{dt}^{2}\right)\right\} \times \mathrm{kx}=\{(\mathrm{dbx}) /(\mathrm{d} \mathrm{t})\}$
(C) $m\left\{\left(d^{2} x\right) /\left(d t^{2}\right)\right\}=k x+\{(d b x) /(d t)\}$
(D) $\left\{\left(\mathrm{md}^{2} \mathrm{x}\right) /\left(\mathrm{dt}^{2}\right)\right\}-\mathrm{kx}=\mathrm{b}\{(\mathrm{d} \mathrm{x}) /(\mathrm{dt})\}$

Narayan Hari

Numerade Educator

Problem 2786

In a damped oscillation with damping constant $b$. The time taken for amplitude of oscillation to drop to half what is its initial value?
(A) $(\mathrm{b} / \mathrm{m}) \ln 2$
(B) (b / $2 \mathrm{~m}) \ln 2$
(C) $(\mathrm{m} / \mathrm{b}) \ln 2$
(D) $(2 \mathrm{~m} / \mathrm{b}) \ln 2$

Narayan Hari

Numerade Educator

Problem 2787

In a damped oscillation with damping constant $b$. The time taken for its mechanical energy to drop to half. What is its value?
(A) $(\mathrm{b} / \mathrm{m}) \ln 2$
(B) $(\mathrm{b} / 2 \mathrm{~m}) \ln 2$
(C) $(\mathrm{m} / \mathrm{b}) \ln 2$
(D) $(2 \mathrm{~m} / \mathrm{b}) \ln 2$

Narayan Hari

Numerade Educator

Problem 2788

For a pendulum in damped oscillation, with a bob of mass $\mathrm{m}$ and radius $\mathrm{r}$, with a string of length $\ell$ What is the time period?
(A) $\mathrm{T}=2 \pi \sqrt{(\ell / \mathrm{g})}$
(B) T depends on $\mathrm{m}$
(C) $\mathrm{T}>2 \pi \sqrt{(\ell / \mathrm{g})}$
(D) $\mathrm{T}<2 \pi \sqrt{(\ell / \mathrm{g})}$

Narayan Hari

Numerade Educator

Problem 2789

In the experiment of simple pendulum, we have taken a thread of $140 \mathrm{~cm}$, and an amplitude of $5 \mathrm{~cm}$ to begin with. Here $\theta$ to begin with is about........
(A) $5^{\circ}$
(B) $8^{\circ}$
(C) $2^{\circ}$
(D) $3^{\circ}$

Narayan Hari

Numerade Educator

Problem 2790

In the experiment of simple pendulum we keep $\theta<5^{\circ}$, so as ensure $\ldots \ldots \ldots$
(A) mass $\mathrm{m}$ does not interfere in the time period
(B) $\mathrm{g}$ remains constant
(C) the air drag is not too much
(D) $\sin \theta \cong \theta$ where by motion becomes simple harmonic.

Narayan Hari

Numerade Educator