Physics Test-5...

Planck's constant has the dimensions of:

A circular disc of radius \(0.2\) meter is placed in a uniform magnetic field of induction \(\frac{1}{\pi}\left(\frac{Wb}{{m}^{2}}\right)\) in such a way that its axis makes an angle of \(60^{\circ}\) with \(\overrightarrow{{B}}\). The magnetic flux linked with the disc is:

A small piece of metal wire is dragged across the gap between the poles of a magnet in \(0.4 {~s}\). If the change in magnetic flux in the wire is \(8 \times 10^{-4} {~Wb}\), then emf induced in the wire is

If two \(+5 D\), lenses are mounted at some distance apart, the equivalent power will always be negative if the distance is:

The transmission of high frequencies in a coaxial cable is determined by:

In Fraunhofer diffraction experiment, \(L\) is the distance between the screen and the obstacle, \(b\) is the size of obstacle and \(λ\) is the wavelength of the incident light. The general condition for the applicability of Fraunhofer diffraction is:

A radioactive sample \({S}_{1}\) having an activity of \(5 \mu {Ci}\) has twice the number of nuclei as another sample \({S}_{2}\) which has an activity of \(10 \mu {Ci}\). The half-lives of \({S}_{1}\) and \({S}_{2}\) can be:

A transmitter puts out a total power of \(2.09\) Watts of \(30 \%\) AM signal. How much power is contained in each of the sidebands?

A ball is dropped on a smooth horizontal surface from height ‘\(h\)’. What will be the height of rebounce after second impact, if coefficient of restitution between ball and surface is ‘\(e\)’?

What is the velocity of light in a diamond if the refractive index of diamond with respect to vacuum is 2.5?

\(\Delta C _{ P }\) for a reaction is given by \(2.0+0.2 T cal / deg\). Its enthalpy of reaction at \(100 K\) in \(K\) cal will be, if \((\Delta H )_{\text {reac }}\) at \(10 K\) is \(-14.38 K\) cal:

The electric current of an electromagnet is switched off then the magnetic property of the electromagnet will-