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    the equation of a wave is represented by y=10^{-4}\sin(100t-\frac{x}{10^{\circ}})
    what's the value of velocity of wave? options are 100m/s, 4m/s, 1000m's and 0.01m/s.
    i didnt get any of these. i tried solving this way:

    10^{\circ}=\frac{10}{2 \pi}
    \frac{2\pi}{lymda}=\frac{2\pi}{1  0}
    and
    2\pi*f=100
    then substituting value of lymda and f in v=lymda*f
    but the answer didnt match.
    so please can anyone help me?
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    As it has 10 degrees there I guess x must be in degrees, not radians.
    If that is the case, then "omega" in the 100t term would also have to be in degrees per second not radians.

    Does that give a better answer?
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    (Original post by aachal)
    the equation of a wave is represented by y=10^{-4}\sin(100t-\frac{x}{10^{\circ}})
    what's the value of velocity of wave? options are 100m/s, 4m/s, 1000m's and 0.01m/s.
    i didnt get any of these. i tried solving this way:

    10^{\circ}=\frac{10}{2 \pi}
    \frac{2\pi}{lymda}=\frac{2\pi}{1  0}
    and
    2\pi*f=100
    then substituting value of lymda and f in v=lymda*f
    but the answer didnt match.
    so please can anyone help me?
    Think about what the question is asking. Go back to the definition of velocity:

    Velocity = rate of change of distance w.r.t. time.

    i.e. v = dy/dt

    Now have another go.
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    physics at university seems so hard.
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    (Original post by uberteknik)
    Think about what the question is asking. Go back to the definition of velocity:

    Velocity = rate of change of distance w.r.t. time.

    i.e. v = dy/dt

    Now have another go.
    I think it wants the velocity in the direction of travel... so vp=w/k
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    (Original post by aachal)
    the equation of a wave is represented by y=10^{-4}\sin(100t-\frac{x}{10^{\circ}})
    what's the value of velocity of wave? options are 100m/s, 4m/s, 1000m's and 0.01m/s.
    i didnt get any of these. i tried solving this way:

    10^{\circ}=\frac{10}{2 \pi}
    \frac{2\pi}{lymda}=\frac{2\pi}{1  0}
    and
    2\pi*f=100
    then substituting value of lymda and f in v=lymda*f
    but the answer didnt match.
    so please can anyone help me?
    so, we know that vp=w/k I think it's just a case of they've given unusual units and that w and k are in */s and corresponding units for k rather than radians
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    (Original post by natninja)
    so, we know that vp=w/k I think it's just a case of they've given unusual units and that w and k are in */s and corresponding units for k rather than radians
    ow yeah!you might be right.then we get v=1000m/s.thanks for the help.
 
 
 
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