in terms of wave is i complete 5 cycles within 2 seconds then which one is which

I'm sorry, but your question is not clear. Could you please provide more details or rephrase it? If you're asking about wave frequency and period, here's a general explanation:

1. A cycle in a wave is one complete wave oscillation or one complete wave, from crest to crest or trough to trough.

2. The time it takes for one complete cycle is called the period of the wave. It's usually denoted by the letter 'T' and measured in seconds.

3. The frequency of a wave is the number of cycles that occur in one second. It's usually denoted by the letter 'f' and measured in Hertz (Hz).

So, if a wave completes 5 cycles in 2 seconds:

1. The period of the wave (T) would be the total time divided by the number of cycles. So, T = 2 seconds / 5 cycles = 0.4 seconds/cycle.

2. The frequency of the wave (f) would be the number of cycles divided by the total time. So, f = 5 cycles / 2 seconds = 2.5 Hz.

I hope this helps! If you have a different question or need further clarification, please let me know!