Frames Per Second (FPS) is a measure of how many individual frames (images) are displayed in one second of video or motion picture. It is a critical factor in determining the smoothness and realism of motion in videos, animations, and films. The higher the FPS, the smoother the motion appears to the human eye. Assertion (A) is true: In traditional cinema, 24 frames per second (fps) is the standard frame rate used for motion pictures. This rate is chosen because it is fast enough for the human eye to perceive smooth motion. Reason (R) is false: While persistence of vision is true, the time duration is typically around 1/16 seconds (about 0.0625 seconds), not 0.1 seconds. Directions: The following items consist of two statements, one labeled as the Assertion (A) and the other as Reason (R). You have to answer these items using the code given below. 266. Assertion (A): Small glass beads fixed on traffic signals glow brightly when light falls upon them. Reason (R): Light is totally reflected when the angle of incidence exceeds a certain critical value and light travelling in a denser medium is reflected from a rarer medium. Codes:

Question

YESPYQ · Accepted Answer

Correct answer: Both A and R are true and R is the correct explanation of A. Assertion (A) is true: The glass beads on traffic signals are designed to reflect light efficiently. When light hits them, they undergo a reflective process, causing the beads to glow brightly and making the signal more visible from various angles. Reason (R) is true: This describes the phenomenon of total internal reflection (TIR), which occurs when light moves from a denser medium (like glass) to a rarer medium (like air) and the angle of incidence exceeds the critical angle. In the case of the glass beads, light entering the bead at a steep angle is totally internally reflected, making them glow brightly. Thereby, Reason (R) correctly explains Assertion (A). 267

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