Assuming oblique angle of incidence, what will the angle of transmission be if the propagation speed of medium 1 is greater than that of medium 2?

• A. Greater than the angle of incidence
• B. Less than the angle of incidence
• C. Equal to the angle of incidence
• D. Propagation speed does not influence the angle of transmission

Answer: (B)

When light travels from one medium to another at an oblique angle, the relationship between the angles of incidence and transmission is governed by Snell's Law, which states that the ratio of the sines of the angles is equal to the ratio of the velocities in the two media. Mathematically, this can be expressed as:

[

\frac{\sin(\theta_1)}{\sin(\theta_2)} = \frac{v_1}{v_2}

]

where ( \theta_1 ) is the angle of incidence, ( \theta_2 ) is the angle of transmission (or refraction), ( v_1 ) is the speed of light in medium 1, and ( v_2 ) is the speed of light in medium 2.

In this scenario, when the propagation speed of medium 1 is greater than that of medium 2 (meaning ( v_1 > v_2 )), Snell's Law implies that the angle of transmission ( \theta_2 ) must be less than the angle of incidence ( \theta_1 ). This is because a higher speed in the first medium leads to a greater angle associated with the same sine function compared to the