MCQ
If the phase difference between alternating current and e.m.f. is $\phi$, then the value of power factor is :
  • $cos~\phi$
  • B
    $cos^{2}\phi$
  • C
    $sin~\phi$
  • D
    $tan\phi$

Answer

Correct option: A.
$cos~\phi$
A

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

In a region of uniform magnetic induction , a circular coil of radius 30 cm and resistance ohm is rotated about an axis which is perpendicular to the direction of B and which forms a diameter of the coil. If the coil rotates at 200 rpm the amplitude of the alternating current induced in the coil is

(a) mA

(b) 30 mA

(c) 6 mA

(d) 200 mA

Which of the following particles will describe the smallest circle when projected with the same velocity perpendicular to a magnetic field?

For what value of R the net resistance of the circuit will be 18 ohms

(a) 8 Ω     

(b) 10 Ω

(c) 16 Ω   

(d) 24 Ω

Equal charges q are placed at the vertices A and B of an equilateral triangle ABC of side a. The magnitude of electric field at the point C  is

(a)  

(b)

(c)

(d)

An air bubble in sphere having 4 cm diameter appears 1 cm from surface nearest to eye when looked along diameter. If amg = 1.5, the distance of bubble from refracting surface is

(a) 1.2 cm

(b) 3.2 cm

(c) 2.8 cm

(d) 1.6 cm

1 Volt = _____________ style-type: lower- alpha;”>
Flux associated to a coil at any instant $t$ is $\phi=10 r^2$ $50 t+250$, then induced emf at $t =3$ is :
Stopping potential is the negative voltage on the collector plate at which the photoelectric current just becomes __________.
Identify which of the following should be used for polarised light waves?
I. Sunglasses
II. Remove ultraviolet light
III. Reveal stress patterns

In the disintegration series   The value of Z and A respectively will be

(a) 92, 236

(b) 88, 230

(c) 90, 234

(d) 91, 234