Q: Why does g vary from poles to equator?
A: Because Earth is not a perfect sphere – its radius increases from poles to equator, affecting the gravitational force.
Q: What is the SI unit of pressure?
A: Pascal (Pa) or N/mĀ².
Q: Why do sharp knives cut better than blunt ones?
A: Sharp knives have a smaller surface area, creating greater pressure with the same force.
Q: What is the formula for weight?
A: Weight = mass Ć acceleration due to gravity (W = mg)
Q: What is the universal gravitational constant (G)?
A: G = 6.673 Ć 10ā»Ā¹Ā¹ N mĀ²/kgĀ²
Q: Why don’t we feel the gravitational force between two people?
A: Because gravitational force is very weak unless large masses are involved.
Q: What keeps the moon orbiting around Earth?
A: The gravitational force between Earth and the moon.
Q: What is the formula for gravitational force between two objects?
A: F = G(māmā)/dĀ², where mā and mā are masses and d is the distance between them.
Q: Why does an apple fall toward Earth rather than Earth moving toward the apple?
A: While both attract each other, Earth’s much greater mass results in negligible acceleration compared to the apple’s acceleration.
Q: How does gravitational force change when distance between objects is doubled?
A: When the distance is doubled, the gravitational force becomes one-fourth (1/4) of its original value, as force is inversely proportional to the square of distance.
