Question

sendo so =100 m , vo =10 m/s e a = -10 m/s² , determinar a velocidade para:
a -S= -125
b- S=-105
c- S=102
d- S=90

Answer 1

$\boxed{V^2 = V_0^2 + 2 a * d}$

V = velocidade
v0 = velocidade inicial =10
a = aceleraçao =  -10
d = distancia percorrida = S - s0 =  S - 100

então 
$V^2 =10^2+2*(-10)*d\\\\V^2=100-20*d\\\\ \boxed{V= \sqrt{(100-20*d)} }$
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A) S = -125
a distancia percorrida será
d=-125 - 100 =  -225

a velocidade será
$V= \sqrt{(100-20*-225)}\\\\V= \sqrt{100+4500} \\\\V = \sqrt{4600}$
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b) S = -105

d = -105 - 100
d = -205

$V= \sqrt{100-20*-205} \\\\V= \sqrt{100-20*-205} \\\\V= \sqrt{100+4100} \\\\V= \sqrt{4200}$
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c) S =102

d = 102 -100
d = 2

$V= \sqrt{100-20*2}\\\\ V= \sqrt{100-40} \\\\V= \sqrt{60}$
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d) S = 90

d = 90 - 100
d = -10

$V= \sqrt{100-20*-10} \\\\V= \sqrt{100+200} \\\\V = \sqrt{300}$