Final answer:
Using Newton's universal law of gravitation, the force of gravity between the school principal with a mass of 35 kg and the Earth is calculated to be 344 N.
Step-by-step explanation:
To calculate the force of gravity between the school principal and the Earth, we can use Newton's universal law of gravitation, which is given by the formula:
F = G × (m1 × m2) / r^2
Where:
- F is the force of gravity
- G is the gravitational constant (6.674 × 10^-11 N·m²/kg²)
- m1 and m2 are the masses of the two objects
- r is the distance between the centers of the two masses
Inserting the given values, we have:
F = (6.674 × 10^-11 N·m²/kg²) × (35 kg × 6.0 × 10^24 kg) / (6.38 × 10^6 m)^2
Calculating this, we get:
F = (6.674 × 10^-11) × (35 × 6.0 × 10^24) / (6.38 × 6.38 × 10^12)
F = 343.91 N, which rounds to 344 N.
Therefore, the correct answer is b. 344 N.