Pendulum clocks use a pendulum to keep time (Fig. Q11.15). This type of clock can be adj...

Pendulum clocks use a pendulum to keep time (Fig. Q11.15). This type of clock can be adjusted by varying the length of the pendulum. How should the length be adjusted in the following cases?

(a) The clock is running slow.

(b) The clock is running fast.

(c) The clock is running fi ne at sea level, but needs to be moved to Denver.