17
18
19
20
Correct answer is A
The number of images formed = \(\frac{360}{n}\) where the value gotten is odd
else, = \(\frac{360}{n} -1\).
Solving, we have that \(\frac{360}{20} = 18\)
Hence, the no of images formed is 18 - 1 = 17.
1m; 0.25Hz
2m; 0.25Hz
2m; 0.50Hz
4m; 0.50Hz
Correct answer is C
For the 4th harmonic, \(L = 2\lambda\)
\(4m = 2\lambda \implies \lambda = \frac{4m}{2}\)
=\(2m\)
Recall, \(v = f\lambda\)
\(1 = f \times 2 \implies f = \frac{1}{2}\)
= 0.50Hz
41.8°
48.2°
60.8°
90.0°
Correct answer is A
\(\eta = \frac{1}{sin\theta}\)
\(1.5 = \frac{1}{sin\theta}\)
\(sin\theta = \frac{1}{1.5} = 0.667\)
\(\theta = sin^{-1}(0.667) = 41.835°\)
\(\approxeq 41.8°\)
Plane waves through a narrow gap emerge as circular waves. This phenomenon is known as
interference
dispersion
refraction
diffraction
Correct answer is D
Diffraction refers to the various things that occur when a wave encounters an obstacle. This bending of the wave after it passes a small gap is an example of diffraction.
Consider the wave equation: \(y = 10sin(x - 50t)\), What does the number 10 represent?
Acceleration
Speed
Amplitude
Wavelength
Correct answer is C
Comparing the given equation with the wave equation:
\(Asin(kx - \omega t)\), we have that A = 10 which is the amplitude of the wave.
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