Physics 2012 JAMB Past Questions - Question 26: The equation of a wave travelling in a horizontal direction is expressed as y=15sin 2/5(60t-x).What is its wave length ?

Correct Answer

C

Explanation

To find the wavelength of a wave, we need to determine the distance between two consecutive points that are in phase. In the given equation, the wave is expressed as y = 15sin(2/5(60t - x)).

The general equation for a sinusoidal wave is y = A*sin(kx - ωt + φ), where A is the amplitude, k is the wave number, ω is the angular frequency, t is time, x is position, and φ is the phase constant.

Comparing the given equation with the general equation, we can see that k = 2/5 and ω = 60.

The wave number (k) is related to the wavelength (λ) by the equation k = 2π/λ.

Substituting the value of k into the equation, we have 2/5 = 2π/λ.

Simplifying the equation, we get λ = (2π * 5) / 2 = 5π.

Therefore, the wavelength of the wave is 5π units.