You want to construct a pendulum with a period of 4.00 s at a location where g

Question:

You want to construct a pendulum with a period of 4.00 s at a location where g = 9.80 mfs2.
(a) What is the length of a simple pendulum having this period?
(b) Suppose the pendulum must be mounted in a case that is not more than 0.50 m high. Can you devise a pendulum having a period of 4.00 s that will satisfy this requirement?