Question

A transverse wave of amplitude 0.05 m and frequency 250 Hz is travelling along a stretched string with a speed of 100 m/s. What would be the displacement of a particle at a distance 1.1 m origin after 0.02 second?

`[sin  pi/2=1,  cos  pi/2=0]`

पर्याय

• 0.1 m

• 0.15 m

• 0.05 m

• 0.02 m

Answer 1

0.05 m

Explanation:

Equation of a travelling wave is given by y = A sin 27πn`(t-x/"v")`

n = 250 Hz, v = 100 m/s

∴ y = 0.05 sin 500π`(t-x/100)`

For t = 0.02 s and x = 1.1 m

We have y = 0.05 sin 500π`(0.02-1.1/100)`

= 0.05 sin500π`(0.9/100)  `= 0.05 sin4.5π

= 0.05sin`(4+1/2)pi` = 0.05sin`(4pi+pi/2)=0.05sin  pi/2=0.05  "m"`