Question

description
show all you work, including units, on separate paper. follow the \problem solving method\.
this final exam is cumulative and covers material from the entire course.
instructions
from the list of choices, select the one best answer.
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question 59 of 62
1.8 points
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a 25.5 kg child stands on the ground. if he exerts a pressure of 6,250 pa on the ground, what is the contact area of
his shoes?
0.0156 m²
0.156 m²
0.04 m²
0.4 m²

Explanation:

Step1: Find the force exerted

The force exerted by the child is his weight, \( F = mg \), where \( m = 25.5\space kg \) and \( g = 9.8\space m/s^2 \). So \( F = 25.5\times9.8 = 249.9\space N \).

Step2: Use pressure formula to find area

Pressure formula is \( P=\frac{F}{A} \), rearranged to \( A = \frac{F}{P} \). Given \( P = 6250\space Pa \), so \( A=\frac{249.9}{6250}\approx0.04\space m^2 \).

Answer:

\( 0.04\space m^2 \) (corresponding to the option "0.04 m²")