20011 phy MC


1. Please solve the above mc with explanation


2. As it has been mentioned that one of the light experiences pie phase change, then maximum reading (constructive interference) at a point on AB is shown if the path difference equals m(wavelength) instead of (m+1/2)(wavelength?)



I still don't understand the solution to question 44. Could you explain more in detail please?

1 個解答

  • 天同
    Lv 7
    9 年前

    36. When the iron core is removed, value of inductance L decreases. Hence, resonance frequency increases.

    Option A.

    7. Option C


    30. Path traversed = R.[2(theta)], where R is the radius of the circular arc

    Since mv^2/R = qvB

    m is the mass od the particle, q is its charge, v is ts speed, and B is the magnetic flux density.

    i.e. v = qB.R/m

    Time spent in magnetic field = R[2.(theta)]/v = 2R.(theta).m/qBR

    Answer is option D

    13. Wavelength = 4x10^-7 m

    hence, frequency = 3x10^8/(4x10^-7) Hz = 7.5x10^14 Hz

    Answer is option B

    3. Change in potential energy = 10g(1.2/2-0.5/2) J = 70 J

    Option C

    33. Each of the two secondary coils supplies power to the output alternatively.

    Hence, voltage output = 220 x (100/1100) v = 20 v

    Option A

    Microwave experiment:

    Constructive interference: path difference = (m+1/2).入, m = 0, 1,1,3...

    Destructive interference : path difference = m入