Explore topic-wise InterviewSolutions in Current Affairs.

Two sources of sound $S_1$ and $S_2$ vibrate at same frequency and are in phase (figure 16-E8). The intensity of sound detected at a point P as shown in the figure is $I_0$. (a) If $\theta$ equals ${45}^{\circ }$, what will be the intensity of sound detected at this point if one of the sources is switched off? (b) What will be the answer of the previous part if $\theta ={60}^{\circ }$?

A soild cylinder and a hollow cylinder is having same mass $M$. Hollow cylinder is having the outer radius twice to that of solid cylinder. If $I_s$ and $I_h$ are the moment of inertia about the axis, along the height of the solid cylinder and hollow cylinder respectively passing through their centre, find the ratio of $I_h:I_s$.

A block of mass $2kg$ is connected to one end of a system of springs as shown in figure. The springs are massless, having spring constants $k_1=100N/m,k_2=200N/m$, and natural lengths of $0.5m$ each. The other end of the system is fixed at the centre of a frictionless horizontal table. Initially, spring mass system is at rest. If the springs remain horizontal and the mass is made to rotate at an angular speed of half$rev/s$, then the value of spring force $F_1$ and $F_2$ (in newton) are.

A gas is compressed from some initial volume $V_1$ to final volume $V_f$ along two different paths as shown in figure.

If $W_1,W_2$ corresponds to work done during polytropic process of exponents $n_1,n_2$ respectively, then which of the following statements is/are correct ?

A ) what is meaning of gravity and define gravitation.

B) why is gravity have a value 9.8 ms^-2 but not Some 5 or 6 and write its derivevation.

C) write its uses and why is it weaker force than others.

When we use 'g' as positive and negative in motion under gravity.?

Please explain I'm always confused in this.

A thin uniform rod of mass $5\text{kg}$ is rotating about an axis perpendicular to it's plane, passing through midpoint of the rod of length $4\text{m}$. Find the moment of inertia of the rod about this axis.

A heat engine receives $50\text{kcal}$ of heat from the source per cycle, and operates with an efficiency of $20\%$. Find the heat rejected to the sink per cycle.

What vector must be added to the two vectors $\hat{i}-2\hat{j}+2\hat{k}and2\hat{i}+\hat{j}-\hat{k},$ so that the resultant may be a unit vector along x-axis

Electric field due to an uniformly charged ring when x tends to infinity is zero, is it possible practically?

A horizontal force of 100 N pulls two masses 5 kg and 10 kg tied to each other by a light string. What is the tension in the string if the force is applied on 10 kg mass?

In the quadratic equation, $pq{x}^2-(p^2+q^2)x+pq=0,$ then find values of $x$.

Find the co-ordinates of the center of mass of a hollow cone having a height of $90\text{cm}$ as shown in the figure.

Read each statement below carefully, and state, with reasons, if it is true or false;
(a) During rolling, the force of friction acts in the same direction as the direction of motion of the CM of the body.
(b) The instantaneous speed of the point of contact during rolling is zero.
(c) The instantaneous acceleration of the point of contact during rolling is zero.
(d) For perfect rolling motion, work done against friction is zero.
(e) A wheel moving down a perfectly frictionless inclined plane will undergo slipping (not rolling) motion.

Two point masses m and 2m are initially kept at distance $3x_0$. Now they are released and move only under their mutual gravitational interaction force. They collide after time $t_0$. Average speed of particle of mass 2m during this time is $\sqrt{\frac{\alpha Gm}{{\pi }^2{X}_0}}$. Find value of $\alpha$, where $\alpha$ is a constant.

A piece of zinc at a temperature of ${20}^{o}C$ weighing 65.38 g is dropped into 180 g of boiling water $(T={100}^{o}C).$ The specific heat of zinc is $0.4J{g}^{-1\circ }{C}^{-1}$ and that of water is $4.2J{g}^{-1o}{C}^{-1}.$ What is the final common temperature reached by both the zinc and water?

A body of mass 'm' is moving in a straight line at a constant speed 'v'. Its kinetic energy is 'k' and the magnitude of its momentum is 'p'. Which of the following relations is/are correct?

A person stands on a spring balance at the equator. (a) By what fraction is the balance reading less than his true weight ? (b) If the speed of earth's rotation is increased by such an amount that the balance reading is half the true weight, what will be the length of the day in this case ?

The velocity of a particle moving along the positive $x$-axis is given by $v\left(t\right)=-t^3+6t^2+2t$. What is the magnitude of maximum acceleration and also find the time when it is attained?

The free electrons in a conducting wire are in constant thermal motion. If such a wire, carrying no current, is placed in a magnetic field, is there a magnetic force on each electrons? Is there a magnetic force on the wire?

A block is released from a height $h=5m$. After travelling through the smooth curved surface, it moves on the rough horizontal surface through a length $l=8$ $m$ and climbs onto the other smooth curved surface through a height $h^{\prime }$
. If $\mu =0.5$, then $h^{\prime }$ is
$m$.

Work W is required to be done to form a spherical bubble of volume V from a given soap solution. How much work is needed to form a spherical bubble of volume 2V?

A particle is thrown with speed u at angle alpha with the horizontal when the particle makes an angle beta with horizontal its speed will be

A water molecule has a permanent electric dipole moment of magnitude 6 x 10^-30 C-m. estimate the size of the electric field produces at the position of a neighbouring water molecule which is 3 x 10^-9 m away

How many significant figures are there in $0.310\times {10}^5\text{m}$ ?

A wheel is rotating at $900\text{rpm}$ about its axis. When power is cut off, it comes to rest in $60\text{s}$. The angular retardation is $\left(rad/s^2\right)$

Threshold frequency for a metal is ${10}^{15}Hz$. Light of $\lambda =4000\stackrel{\circ }{A}$ falls on its surface. Which of the following statements is correct

What will be the change in the time period of a loaded spring when taken to the moon?

The radius of the first orbit of hydrogen in $0.528\dot{A}$. The radius of second orbit of hydrogen is

Find the potential $V$ of an electrostatic field $\overrightarrow{E}=a(y\hat{i}+x\hat{j}),$ where a is a constant.

The equation of particle executing SHM is $y=20\sin (2\pi t-\frac{\pi }{3})$.
The amplitude $A$, time period $T$ and angular frequency $\omega$ are
[All quantities are in SI units]

Figure (15-E1) shows a wave pulse at t = 0. The pulse moves to the right with a speed of $10cm{s}^{-1}$. Sketch the shape of the string at t = 1 s, 2s and 3s.

A block of mass $M$ is attached to a horizontal spring and is executing SHM, with amplitude $A_1$. When the mass $M$ passes through its mean position, a smaller mass $m$ is placed over it gently and both of them move together with amplitude $A_2$. The ratio of $\left(\frac{A_1}{A_2}\right)$ is