Mary weighs 501 N and she walks down a
flight of stairs to a level 5.2 m below her
starting point.
What is the change in Mary’s potential energy?
Do not listen to the dislikes, its correct
The change in Mary's potential energy can be calculated using the formula:
ΔPE = mgh
where ΔPE is the change in potential energy, m is the mass of the object (in this case Mary) in kilograms, g is the acceleration due to gravity (approximately 9.8 m/s^2), and h is the height (or change in height) in meters.
Given:
Mass of Mary (m) = 501 N (divide by 9.8 to convert it from Newton to kg since weight = mass * gravity)
h = -5.2 m (negative since Mary is going down)
First, let's convert Mary's weight to mass:
m = 501 N / 9.8 m/s^2 ≈ 51.12 kg
Now we can calculate the change in potential energy:
ΔPE = (51.12 kg) * (9.8 m/s^2) * (-5.2 m)
ΔPE ≈ -2647.81 Joules
The change in Mary's potential energy is approximately -2647.81 Joules. Note that the negative sign indicates a decrease in potential energy as she goes down the stairs.
To calculate the change in Mary's potential energy, we need to consider the change in height and the weight of Mary.
The formula to calculate potential energy is:
Potential Energy = Weight x Height
Given that Mary weighs 501 N and she walks down 5.2 m below her starting point, we can substitute these values into the formula:
Potential Energy = 501 N x 5.2 m
To calculate the potential energy, multiply 501 by 5.2:
Potential Energy = 2605.2 N·m (Newton-meters)
Therefore, the change in Mary's potential energy is 2605.2 N·m.