thinner insulation.
greater diameter
smaller diameter
thicker insulation
Correct answer is B
No explanation has been provided for this answer.
Which of the arrangements of radiations below shows decreasing order of wavelengths?
X-rays> radio waves > infrared radiations
Radio waves> infrared radiations > X-rays
Infrared radiations > radio waves > X-rays
X-rays> infrared radiations > radio waves
Correct answer is B
radio waves have a longer wavelength than infrared light, and infrared than x-rays in the electromagnetic spectrum
(3.7, 7.4)
(6.2, 9.9)
(2.5, -4 .8).
(14.7, 1.4)
Correct answer is B
No explanation has been provided for this answer.
I and III only
I, II and IV only
II, III and V only
II and IV only
Correct answer is D
Convex (converging) lenses can form either real or virtual images, whereas concave (diverging) lenses can form only virtual images
Determine the speed of the wave.
64 cm/s
32 cm/s
24 cm/s
72 cm/s
Correct answer is D
Speed = Wavelength x Frequency
or
V = fλ, where frequency = 1/period, f = 1/T.
The period was given as 0.125sec and wavelength = 9cm
: f = 1/T = 1/0125 = 8.
V = fλ = 8 × 9 = 72m/s