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If the resistivity of an alloy is P1 and that of metal is P, then

Resistivity of alloys is generally more than metals.... View Article

When the incident light itself is polarized with electric field vector in the plane of incidence, then if the angle of incidence is θp, there is no

The component of light beam that vibrates perpendicular to the reflecting surface is reflected less as compared to the component parallel to the... View Article

A ray of light strikes a glass plate at an angle of 600. If the reflected and refracted rays are perpendicular to each other, then refractive index of glass is

Brewster's law is defined as the light which receives maximum polarization from a reflecting surface when it is incident to the surface at an... View Article

A ray of light is incident on the surface of glass plate at an angle of incidence equal to Brewster’s angle Ø. If μ represents the refractive index of glass with respect to air, then the angle between the reflected and refracted rays is:

When the light is incident at Brewster's angle, the angle between the reflected ray and refracted ray is 90o, irrespective of the value of... View Article

Eddy currents have negative effects. Because they produce

Eddy currents have negative effect, as they produce heating and damping.... View Article

N resistors each of resistance R are first combined to get minimum possible resistance and then combined to get maximum possible resistance. The ratio of the minimum to maximum resistance is

the maximum resistance is NR and the minimum resistance is R/N, so their ratio is 1/N2... View Article

Kirchhoff’s first law is based on ?

Kirchhoff’s first law states that the sum of the currents meeting at a junction in a closed circuit is zero. Kirchhoff's first law says that... View Article

When a forward bias is applied to a p-n junction, it

In forward biasing the positive terminal of the battery is connected to the the p-side and the negative terminal to the n-side of the p-n... View Article

If the internal resistance of a cell is infinite, the current in the circuit will be

Infinite resistance means no current can flow through it.... View Article

What is the maximum current that can be drawn from a cell of emf E and internal resistance r connected to an external resistance R?

as the maximum current that can be drawn from a cell is for R =0 and it is I = E/r.... View Article

Electromagnetic Spectrum is

Electromagnetic Spectrum is orderly distribution of electromagnetic radiations according to their wavelength or frequency.... View Article

When Wheatstone bridge is in balance condition, the current through galvanometer will be

When the bridge is in balance condition, no current will flow through the galvanometer because potential difference between the two ends of... View Article

What is the origin or source of Visible light

visible light is produced due to atomic excitation.... View Article

A carbon resistance reads Red – Red – Black. What is its resistance?

Value for first colour red is 2 Value for second colour red is also 2 The multiplier for black is 100 Resistance = 22 x 100 = 22 ohm... View Article

Two bulbs one of 50watt and another of 25 watt are connected in series to the mains. Find the ratio of the currents through them.

P = VI = I2R P1/P2 = V1/V2 'I' will be constant here. As the bulbs are in series the same current flows through each of them. Therefore, the... View Article

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