Physics Test - ...

According to the New Cartesian Sign Convention, which one of the following is correct is respect of the formula \(\frac{1}{f}=\frac{1}{v}+\frac{1}{u}\), where symbols have their usual meanings?

A screw gauge has least count of \(0.01 \mathrm{~mm}\) and there are \(50\) divisions in its circular scale.The pitch of the screw gauge is:

Let the length of a potentiometer wire be \(10 {~cm}\) and cell of emf \(E\) is balanced at a length \(\frac{10 }{ 3} {~cm}\) from the positive end of the wire. If the length of the wire is increased by \(5 {~cm},\) at what distance (in \({cm}\) ) from positive end will the same cell give a balance point?

The current in the toroid of average radius r and number of turns N is I, then magnetic field intensity B inside the toroid is related to the average radius r as:

Find the magnitude of the resultant force on a charge of \(1 \mu C\) held at \(P\) due to two charges of \(+2 \times 10^{-8} C\) and \(-10^{-8} C\) at \(A\) and \(B\) respectively.

Given, \(A P=10 cm\)

And, \(B P=5 cm\)

\(\angle A P B=90^{\circ}\)

The image we see in plane mirror is:

Heating effect produced by current is due to the ________.

Potential gradient is defined as:

When photons of wavelength λ1 are incident on an isolated sphere, the corresponding stopping potential is found to be V. When photons of wavelength λ2 are used, the corresponding stopping potential was thrice that of the above value. If light of wavelength λ3 is used then find the stopping potential for this case.

A point charge \(+10 \mu {C}\) is at a distance of \(5 {~cm}\) directly above the centre of a square of side \(10 {~cm}\), as shown in Fig. What is the magnitude of the electric flux through the square? (Hint: Think of the square as one face of a cube with edge \(10 {~cm}\) ).