Atividade 1 - Um caminhão de 20 m de comprimento desenvolve uma velocidade constante numa estrada retilínea e plana. Ele demora 10 s para atravessar uma ponte de 180 m de extensão. Calcule a velocidade do caminhão, em km/h.

   v = 64.8 km / h

Explanation:

This is a uniform rectilinear motion exercise, the speed is

        v = d / t

where d is the distance traveled and t the time to travel the distance

the bridge has d = 180 m and runs it at t = 10 s, we use a reference point on the truck for measurement

    V = 180/10 .v = 18 m / s

we reduce to km / h

    v = 18 m / s (1 km / 1000m) (3600 s / 1 h)

     v = 64.8 km / h

c. rb

explanation:

the atomic radius of a chemical element is a measure of the size of its atoms, usually the mean or typical distance from the center of the nucleus to the boundary of the surrounding shells of electrons.

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