At what place on the earth surface in the weight of body in (a) Maximum (b) Minimum
Answers
The top of a mountain. Especially mountains over 25,000 feet. You are literally farther from the center of gravity and thus weigh less, surprisingly, close to 1% less than sea level. Also correct me if I'm wrong but the equator makes you spin, so it either makes you lighter from this or because Earth is slightly oblate, heavier when on the equator-I forget which one it is. When a plane flies east at 3 mach it becomes slightly heavier, counterwise, a fast enough speed, around 30 mach, flying west, will be so fast it would weigh nothing and zip off into space.
Most planes can not fly 30 times the speed of sound so this is rare. Ion or plasma propulsion might make this a reality though, and, with the recent invention of railguns, it is likely the spin of the earth will need calculation as some projectiles will reach over 8,000 miles per hour, when added to the spin of earth by shooting west, they will weigh enough less than normal that typical gravity will play less of a role and it will not have an even curve, missiles have jets and fins that can correct this problem at high speeds, but fault in projectiles go faster than missiles and have no fins so once fired they have to land were an unpredictable amount of gravity will take them.