The Earth exerts an 640 N gravitational force
on a man. What force does the man exert on the Earth? Answer in units of N.
According to Newton's third law of motion, for every action, there is an equal and opposite reaction. In this case, the Earth exerts a gravitational force of 640 N on the man, so the man also exerts an equal and opposite force on the Earth. Therefore, the force that the man exerts on the Earth is also 640 N.
To find the force that the man exerts on the Earth, we can use Newton's third law of motion, which states that for every action, there is an equal and opposite reaction.
The force of gravity between two objects can be calculated using the formula:
F = G * ((m1 * m2) / r^2)
Where:
F = force of gravity
G = gravitational constant (approximately 6.67430 × 10^-11 N(m/kg)^2)
m1 = mass of the first object
m2 = mass of the second object
r = distance between the two objects' centers of mass
In this case, the first object is the Earth and the second object is the man. Since the Earth's mass is much larger than the man's mass, we can consider the man's mass negligible compared to the Earth's mass.
Given that the gravitational force exerted by the Earth on the man is 640 N, we can set up the equation:
640 N = G * ((mass of the Earth * mass of the man) / r^2)
Since the mass of the man is negligible compared to the Earth's mass, we can ignore it in this calculation. Let's assume the distance between the Earth and the man is r = 1 meter for simplicity.
Plugging in the values, we can solve for the force that the man exerts on the Earth:
640 N = G * ((mass of the Earth * mass of the man) / (1 m)^2)
Rearranging the equation to solve for the force that the man exerts on the Earth:
Force that the man exerts on the Earth = (640 N * (1 m)^2) / mass of the Earth
The exact numerical value will depend on the mass of the Earth, which is approximately 5.972 × 10^24 kilograms.
Therefore, the force that the man exerts on the Earth can be calculated using the above equation.