Question Detail

PHY 104 PHY 104 Past Questions Objective Question

Question

Two waves, same frequency and same wavelength, each of amplitude 2 cm are superimposed. If the phase difference between them is 30°, calculate the amplitude of the resulting wave. The formula for resultant displacement is y = 2Acos(φ/2)sin(ωt-kx+φ/2).
Options
A 4.83 cm
B 3.97 cm
C 3.86 cm
Correct Answer
D 3.73 cm
Correct Answer

Option C is the correct answer.

Detailed Explanation

For two waves of equal amplitude A undergoing superposition with a phase difference φ, the resultant amplitude (R) is given by the formula R = 2A|cos(φ/2)|.Given:Amplitude A = 2 cmPhase difference φ = 30°Substitute the values into the formula:R = 2 * (2 cm) * cos(30°/2)R = 4 cm * cos(15°)R = 4 cm * 0.9659R ≈ 3.8636 cmRounding to two decimal places, the amplitude of the resulting wave is approximately 3.86 cm.

Hint

The resultant amplitude (R) for two waves of equal amplitude A with a phase difference φ is R = 2A|cos(φ/2)|.

Question Info