Question

you can complete this review up to 3 times. it will be worth 2.5 points extra credit onto the exam.
question 7
1 pts
a person has a mass of 61 kg. when they are at rest, standing on level ground, what must be the magnitude of the normal force that the ground exerts on them?

Explanation:

Step1: Recall Newton's First Law and Weight Formula

When an object is at rest (in equilibrium), the net force acting on it is zero. For a person standing on level ground, the normal force (\(F_N\)) exerted by the ground upward balances the weight (\(W\)) of the person downward. The weight of an object is given by \(W = mg\), where \(m\) is the mass and \(g\) is the acceleration due to gravity (approximately \(9.8\ m/s^2\)).

Step2: Substitute Values into the Weight Formula

Given \(m = 61\ kg\) and \(g = 9.8\ m/s^2\), we calculate the weight (which equals the normal force in this case, since the person is in equilibrium):
\(F_N=W = mg=(61\ kg)\times(9.8\ m/s^2)\)

Step3: Perform the Multiplication

\(61\times9.8 = 597.8\)

Answer:

\(597.8\ N\) (or approximately \(600\ N\) if using \(g = 10\ m/s^2\), but the standard value gives \(597.8\ N\))