Power of a power

Statements: All forces are energies. All energies are powers. No power is heat. Conclusions: I. Some forces are definitely not powers. II. No heat is force.

Assertion: When AC circuit contain resistor only, its power is minimum. Reason: Power of a circuit is independent of phase angle.

In a half wave rectifier output is taken across a 90 ohm load resistor. If the resistance of diode in forward biased condition is 10 ohm , the efficiency of rectification of ac power into dc power is.

In a full wave rectifier output is taken across a load resistor of 800 ohm . If the resistance of diode in forward biased condition is 200 ohm , the efficiency of rectification of ac power into dc power is.

Emissive power of any surface (e), Absorptive power (a), Reflecting power (r) and transmission power (t) are related as –

Define magnifying power and resolving power of a telescope.

Define absorptive power and emissive power of a body.

For circuits used for transporting elecrtric power, a low power factor impleis larger power loss in transmission. Explain?

Which of the following has the highest value? (a)10 power 11 (b)12 power 9 (c)5 power 5 (d)11 power 10

The ratio of secondary to primary turns is 4:5. if power input is P, then the ratio of power output to power input is