The reactance of a capacitor is 40 k ohm at a frequency of 0

The reactance of a capacitor is 4.0 k ohm at a frequency of 0.60 kHz. What is the capacitance? 0.42 mu F 2.6 mu F0.090 mu F 0.066 mu F What is the wavelength used by a radio station that broadcasts at a frequency of 920 kHz? (c= 3.00 times 10^8 m/s) 226 m 326 m 175 m 276 m 22.6 m Which one of the following lists gives the correct order of the electromagnetic waves from waves from longer wavelength to shorter wavelength? radio waves, microwaves, visible, x-rays, infrared, ultraviolet, gamma rays radio waves, microwaves, infrared, visible, ultraviolet, x-rays, gamma rays radio waves, infrared, microwaves, ultraviolet, visible, x-rays, gamma rays radio waves, infrared, x-rays, microwaves, ultraviolet, visible, gamma rays radio waves, ultraviolet, x-rays, microwaves, infrared, visible, gamma rays If a diffraction grating is heated (without damaging it) and therefore expands, what happens to the angular location of the first-order maximum? It moves away from the centerline. It doesn\'t change. It moves toward the centerline. A single-slit diffraction pattern is formed on a distant screen. Assuming the angles involved are small, by what factor will the width of the central bright spot on the screen change if the wavelength of the illuminating light is doubled? It will become four times as large. It will double. It will be cut in half. It will become eight times as large. It will be cut to one-quartet its original size. An AC circuit consists of a resistance of 13.0 k ohm, a capacitance of 7.0 mu F, and an inductance of 35.0 H, all connected in series. Draw the circuit diagram for this circuit. What frequency is needed to minimize the impedance if the voltage amplitude is 110 V? 12 kHz 0.064 kHz 2.1 kHz 0.010 kHz A light beam with wavelength 500 nm is reflected constructively from a thin layer of oil having index of refraction 1.25. The oil floats on the top of water of 1.33. What is the phase shift due to reflection for the ray reflected of the top of the oil layer? What is the minimum thickness of the layer of oil? 225 nm 200 nm 175 nm 150 nm 100 nm

Solution

1) Reactance due to capacitor,

Xc = 1/ (2 pi f C)

4 x 10^3 = 1 / (2 x pi x 0.60 x 10^3 x f )

f = 6.6 x 10^-8 F OR 0.066 uF

Ans(D)

2) wavelength = v / f = (3 x 10^8) / (920 x 10^3 ) = 326 m

Ans(B)

3) lower frequency means higher wavelength and vice versa.

rADIO, microwave, infrared, visible, Ultraviolet, XRay, Gamma

Ans(B)

(4) y = m * lamda * D / a

diffraction grating is heated then a will increase.

so distance from centrline will decrease.

so it moves towards the centreline.

ANs(C)

(5) width of central bright spot = lambda *D / a

lambda is doubled then width also doubled.

Ans(B)