A small rock with mass 0.12 is fastened to a massless string with length 0.80 to form a pendulum. The pendulum is swinging so as to make a maximum angle of 45 with the vertical. Air resistance is negligible.
A- What is the speed of the rock when the string passes through the vertical position?
B- What is the tension in the string when it makes an angle of 45 with the vertical?
C- What is the tension in the string as it passes through the vertical?