Physics Test-3...

If a stone of mass \(m\) is rotated in a vertical circular path of radius 1 meter, the critical velocity will be:

One end of a nylon rope of length \(4.5 \mathrm{~m}\) and diameter \(6 \mathrm{~mm}\) is fixed to a free limb. A monkey weighting \(100 \mathrm{~N}\) jumps to catch the free end and stays there. Find the elongation of the rope. (Given Young's modulus of nylon \(=4.8 \times 10^{11} \mathrm{Nm}^{-2}\) and Poisson's ratio of nylon \(=0.2\) )

Which of the following statement is false for the properties of electromagnetic waves?

If the kinetic energy of a body is increased nine times then the momentum of the body will be increased by:

A boy is pedaling a stationary bicycle that is attached to a coil of area \(0.7 \mathrm{~m}^{2}\). The coil consists of \(100\) turns. The coil is rotating at the rate of 60 revolutions per minute and placed in a uniform magnetic field of \(0.02 \mathrm{~T}\). The field is perpendicular to the axis of rotation of the coil. Find the maximum emf generated in the coil.

When a simple pendulum is rotated in a vertical plane with constant angular velocity, the centripetal force is?

The escape velocity of a body does not depend upon:

A car is moving with uniform acceleration covers \(450\) m in a \(5\) second interval and further, it covers \(700\) m in a \(10\) second interval. The acceleration of the car is__________.

If \(v=\frac{A}{t}+B t^{2}+C t^{3}\) where \(v\) is velocity, \(t\) is time and \(A, B\) and \(C\) are constants, then the dimensional formula of \(B\) is:

For which of the following pair of resistors, the balancing length is not 0.25 m in a meter bridge?

A charge of \(2 \mu \mathrm{C}\) is placed at the origin. Find the increase in the electrostatic potential energy of the system of all charges, if a \(1 \mu \mathrm{C}\) charge and \(\mathrm{a}-1 \mu \mathrm{C}\) charge are brought from infinity to \(\mathrm{A}(1,0)\) and \(\mathrm{B}(-1,0)\) respectively.

A pure inductor \(A\) is connected to an \(AC\) source of \(220 \mathrm{~V}\). When the inductor \(A\) is replaced with another pure inductor \(B\), then the current in the circuit becomes double. Find the ratio of the inductive reactance of the inductor \(A\) to inductor \(B\).

A Proton and an alpha particle both are accelerated through the same potential difference. The ratio of corresponding de-Broglie wavelengths is:

A message signal of frequency 20 kHz is modulated by a carrier wave of frequency 3 MHz. Find the side bands produced.

The ratio of the number of turns and the radius of two coils is \(1: 3\) and \(3: 1\) respectively. If the same current is flowing in both the coils, then find the ratio of the magnetic field at the centre of the coils.