Electric Charges and Fields — Physics STD 12 Science — Question

If in the experiment of Wheatstone’s bridge, the positions of cells and galvanometer are interchanged, then balance point will:

The molecules having permanent electric dipole moment even in the absence of electric field are called as:

By placing the prism in minimum deviation position, images of the spectrum(a) Becomes inverted(b) Becomes broader(c) Becomes distinct(d) Becomes intensive

Direction of induced emf is determined by:

A torch battery consisting of two cells of 1.45 volts and an internal resistance 0.15Ω, each cell sending currents through the filament of the lamps having resistance 1.5ohms. The value of current will be(a) 16.11 amp(b) 1.611 amp(c) 0.1611 amp(d) 2.6 amp

If no external voltage is applied across P-N junction, there would be(a) No electric field across the junction (b) An electric field pointing from N-type to P-type side across the junction(c) An electric field pointing from P-type to N-type side across the junction(d) A temporary electric field during formation of P-N junction that would subsequently disappear

In a vacuum diode, the space around the cathode which is filled with electrons, is called ________:

The band gap in Germanium and silicon in eV respectively is(a) 0.7, 1.1(b) 1.1, 0.7(c) 1.1, 0 (d) 0, 1.1

While using an electric bulb, the reflection for street lighting should be from(a) Concave mirror(b) Convex mirror(d) Parabolic mirror(d) Parabolic mirror