Correct Answer: Option B) 2 only
Earth's gravity is not uniform throughout the planet and varies based on several factors. Let me explain each statement:
Statement 1: Gravity is uniform throughout the planet - This is Incorrect. Gravity varies across Earth's surface due to several factors:
Altitude: Gravity decreases with height above sea level
Latitude: Gravity varies from equator to poles
Local geology: Dense rock formations increase local gravity
Earth's rotation: Centrifugal force affects gravitational pull
Statement 2: Gravity is weaker at the equator than at the poles - This is correct. This happens due to two main reasons:
Earth's shape: Earth is an oblate spheroid (flattened at poles, bulging at equator). The equator is about 21 km farther from Earth's center than the poles, making gravity weaker there.
Centrifugal force: Earth's rotation creates centrifugal force that partially counteracts gravity. This effect is maximum at the equator and zero at the poles.
The difference in gravitational acceleration between poles and equator is approximately 0.5%, with gravity being about 9.78 m/s² at the equator and 9.83 m/s² at the poles.
