Before beginning, I recommend that you understand Pendulum by clicking here and understand Moment of Inertia by clicking here, since questions are asked from them.
Which is better between Kater’s Pendulum and Bar Pendulum? Why?
Kater’s pendulum is generally considered superior to a bar pendulum for accurate gravity measurements because it eliminates the effects of air resistance and friction by using a knife-edge suspension and a reversible pendulum. However, Bar Pendulum is simpler to construct and use, making it more suitable for rough measurements.
To view detailed experiment with derivations, click here.