KCET 2025 Physics Paper

In this problem, we are given two angles, r and r1, inside a prism with an angle of 50∘. The angle r changes with time according to the equation r=10∘+t2.
To find out how r1 changes with time, we follow these steps:
Since the sum of angles r and r1 inside the prism must equal the prism's angle, we write:
r+r1=50∘
Substitute the expression for r into the equation:
(10∘+t2)+r1=50∘
Solve for r1 :
r1=50∘−10∘−t2=40∘−t2
Therefore, during the time interval considered, the angle r1 varies with time as 40∘−t2.