When two waves of almost equal frequency $\mathrm{n}_{1}$ and $\mathrm{n}_{2}$ are produced simultaneously, then the time interval between succesive maxima is

• A

  $\frac{1}{n_{1}+n_{2}}$
• B

  $\frac{1}{n_{1}}+\frac{1}{n_{2}}$
• C

  $\frac{1}{n_{1}}-\frac{1}{n_{2}}$
• Correct answer
  D

  $\frac{1}{n_{1}-n_{2}}$

Hence, the correct answer is option: 'D'.