The given graph illustrates a transverse wave travelling on a string at a particular instant, and the points P, Q, R and S represent element of the string. Which of the following statements about the motion of the element of the correct?
| A. |
The speed of the element at P is a maximum |
| B. |
The displacement of the element at Q is always zero |
| C. |
The energy of the element at R is entirely kinetic |
| D. |
The acceleration of the element at S is maximum |
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