Question 358: Wave Optics

Question

In biprism experiment, $$6^{	ext {th }}$$ bright band with wavelength '$$\lambda_1$$' coincides with $$7^{	ext {th }}$$ dark band with wavelength '$$\lambda_2$$' then the ratio $$\lambda_1: \lambda_2$$ is (other setting remains the same)

Accepted Answer

Distance of $$6^{	ext {th }}$$ bright band $$=\frac{6 \lambda_1 \mathrm{D}}{\mathrm{d}}$$
Distance of $$7^{	ext {th }}$$ dark band $$=\frac{6.5 \lambda_2 \mathrm{D}}{\mathrm{d}}$$
$$	herefore \frac{3 \lambda_1 \mathrm{D}}{\mathrm{d}}=\frac{6.5 \lambda_2 \mathrm{D}}{\mathrm{d}}, \quad 	herefore \frac{\lambda_1}{\lambda_2}=\frac{6.5}{6}=\frac{13}{12}$$

Answer

$$7: 6$$

Answer

$$13: 12$$

Answer

$$12: 13$$

Answer

$$6: 7$$

Wave Optics

In biprism experiment, $6^{\text {th }} bright band with wavelength '\lambda_1' coincides with 7^{\text {th }} dark band with wavelength '\lambda_2' then the ratio \lambda_1: \lambda_2$ is (other setting remains the same)

Choose the correct answer: