Four identical pendulums hang at rest but in different locations.
• Location W: sea level, Earth’s surface gravity gE=9.8m/s2
• Location X: top of a 4 km-high mountain on Earth where g is slightly smaller
• Location Y: bottom of a deep mine shaft on Earth where g is slightly larger
• Location Z: a planet where g is exactly half of Earth’s surface value
Assuming each pendulum is given the same small initial displacement, which location will result in the pendulum having the longest period?
(a) Location Y
(b) Location Z
(c) Location X
(d) Location W