Question 507: Waves

Question

A wave in a string has an amplitude of 2 cm. The wave travels in the +ve direction of x axis with a speed of 128 m/s. and it is noted that 5 complete waves fit in 4m length of the string.  The equation describing the wave is

Accepted Answer

As $$A = 2cm,{\omega  \over k} = 128m{s^{ - 1}}$$,
$$5\lambda  = 4 $$, $$ \lambda  = {4 \over 5}m$$
y = A sin (kx Ã¢ÂÂ $$\omega $$t)
$$k = {{2\pi } \over \lambda } = {{2\pi  	imes 5} \over 4} = {{31.4} \over 4} = 7.85$$
$$ 	herefore $$ $$\omega $$ = 128 ÃÂ 7.85 = 1005
so y = 0.02 m sin (7.85x Ã¢ÂÂ 1005 t)

Answer

y = (0.02) m sin (15.7 x $$-$$ 2010t)

Answer

y = (0.02) m sin (15.7 x + 2010t)

Answer

y = (0.02) m sin (7.85 x $$-$$ 1005t)

Answer

y = (0.02) m sin (7.85 x + 1005t)

Waves

A wave in a string has an amplitude of 2 cm. The wave travels in the +ve direction of x axis with a speed of 128 m/s. and it is noted that 5 complete waves fit in 4m length of the string. The equation describing the wave is

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