Question

Imagine a 55 kg person whose two feet cover an area of 500 cm2. What is the pressure applied to the ground by his feet?
Group of answer choices

27,500 Pa

100,440 Pa

1,860 Pa

10,780 Pa

Answer 1

To calculate the pressure applied to the ground by the person's feet, you can use the formula:

\[
\text{Pressure} = \frac{\text{Force}}{\text{Area}}
\]

In this case, the force is the weight of the person, which can be calculated using the formula:

\[
\text{Force} = \text{mass} \times \text{gravity}
\]

Assuming standard gravity (approximately \(9.81 \, \text{m/s}^2\)):

1. Calculate the weight (force):
\[
\text{Force} = 55 \, \text{kg} \times 9.81 \, \text{m/s}^2 = 539.55 \, \text{N}
\]

2. Convert the area from cm² to m²:
\[
500 \, \text{cm}^2 = 500 \times 10^{-4} \, \text{m}^2 = 0.05 \, \text{m}^2
\]

3. Now, calculate the pressure:
\[
\text{Pressure} = \frac{539.55 \, \text{N}}{0.05 \, \text{m}^2} = 10,791 \, \text{Pa}
\]

Rounding this to a suitable number of significant figures gives approximately \(10,780 \, \text{Pa}\).

So the correct answer is:

**10,780 Pa**