Question

Questão 1

Uma pessoa, correndo, percorre 4,0 km com velocidade escalar média de 12 km/h. O tempo do

percurso é de:

a) 3,0 min

b) 8,0 min

c) 20 min

d) 30 min

e) 33 min​

Answer 1

Resposta:

Δs=4,0 km

vm=12 km/h

Δt=?

vm=Δs/Δt

Δt=Δs/vm

Δt=4/12=1/3 h x 60 =20 min

Explicação:

Answer 2

$\large{\begin{array}{l}\sf V=\dfrac{\Delta S}{\Delta t}\Rightarrow\Delta t=\dfrac{\Delta S}{V}\\\\\sf \Delta t=\dfrac{4}{12}\\\\\sf \Delta t\approx0{,}333\,h\\\\\sf 1\,h\rightarrow60\,min\\\sf 0{,}333\,h\rightarrow t\\\\\sf t=\dfrac{60\cdot0{,}333}{1}\\\\\boxed{\boxed{\sf t\approx 20\,min}}\leftarrow\textsf{Letra C}\end{array}}$