Answer:
Explanation:
Given
Weight of Person [tex]W=5.20\times 10^{2} N[/tex]
Cave is [tex]h=35.1 m[/tex] deep
Breaking stress [tex]T=569 N[/tex]
Net Force on Person
[tex]F_{net}=569-520=49 N[/tex]
[tex]a_{net}=\frac{F_{net}}{\frac{W}{g}}[/tex]
[tex]a_{net}=\frac{49}{\frac{520}{9.8}}[/tex]
[tex]a_{net}=0.923 m/s^2[/tex]
The shortest time such that the person can be taken out of cave
[tex]h=ut+\frac{1}{2}at^2[/tex]
where
h=distance moved
t=time
a=acceleration
[tex]35.1=0+\frac{1}{2}(0.923)(t)^2[/tex]
[tex]t^2=76.05[/tex]
[tex]t=\sqrt{76.05}[/tex]
[tex]t=8.72\ s[/tex]
