KCET 2025 Physics Paper

In this problem, we are given two angles, $r$ and $r^1$, inside a prism with an angle of $50^{\circ}$. The angle $r$ changes with time according to the equation $r=10^{\circ}+t^2$.To find out how $r^1$ changes with time, we follow these steps:Since the sum of angles $r$ and $r^1$ inside the prism must equal the prism's angle, we write:$r+r^1=50^{\circ}$ Substitute the expression for $r$ into the equation:$(10^{\circ}+t^2)+r^1=50^{\circ}$Solve for $r^1$ :$r^1=50^{\circ}-10^{\circ}-t^2=40^{\circ}-t^2$Therefore, during the time interval considered, the angle $r^1$ varies with time as $40^{\circ}-t^2$.