What are waves?
3 marks · NormalA student strikes one end of a long metal bar, producing waves that travel along the bar. The distance from the impact point to the other end is 12 m. The waves travel at 600 m/s.
Calculate the time taken for the wave to reach the far end of the bar.
State the unit for your answer in part (a).
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
Show answer
(a) 0.02 s · must show Show working: t = distance / speed
(b) second (s)
Common mistakes: Wrong speed-time-distance formula; Forgetting to use the correct unit
Show mark scheme and worked solution
Marking points
M1 (a) · 1 mark · Selects the correct formula: time = distance / speed. (follow-through)
A1 (a) · 1 mark · Performs calculation correctly: 12 / 600 = 0.02. (follow-through)
B1 (b) · 1 mark · States the correct unit: second or s.
Worked solution
Time taken = distance / speed = 12 m / 600 m/s