Final answer:
John's mass can be calculated using the force of gravitational attraction the Earth exerts on him. By rearranging the equation F = (G * m1 * m2) / (r^2), we can solve for m2 to find John's mass. Using the given values, John's mass is 5.97 × 10^24 kg.
Step-by-step explanation:
According to Newton's universal law of gravitation, the force of gravitational attraction between two objects is given by the equation F = (G * m1 * m2) / (r^2), where F is the force of attraction, G is the gravitational constant, m1 and m2 are the masses of the two objects, and r is the distance between the centers of the objects.
In this case, the force of gravitational attraction between the Earth and John is given as 850 N. John's mass can be calculated by rearranging the equation as m2 = (F * r^2) / (G * m1).
Using the values G = 6.674 × 10^-11 N·m²/kg², r = 6.38 × 10^6 m, and the mass of the Earth is 5.97 × 10^24 kg, we can substitute these values into the equation to find John's mass.
Equation:
m2 = (850 N * (6.38 × 10^6 m)^2) / (6.674 × 10^-11 N·m²/kg² * 5.97 × 10^24 kg)
Calculating:
m2 = 5.97 × 10^24 kg