Question

1. Un móvil se desplaza 20m e invierte 8 segundos en hacerlo. ¿Cuál es su velocidad instantánea? 2. Un móvil parte a 3 metros después del origen y se detiene a 2 metros antes de este. Si demora 10 segundos en su desplazamiento. Calcular su rapidez.

Answer 1

1) v = 2.5 m / s, 2) v = -0.5 m / s

Step-by-step explanation:

For this exercise we will use the kinematics relations

1) velocity is defined by

v =
`(dx)/(dt)`dx / dt

this definition serves for the instantaneous and the average velocity if the displacements are linear in time

v = 20/8

v = 2.5 m / s

b) for this part we use

v =
`(\Delta x)/(\Delta t)`

Δx = x_f -x₀

we must place a reference system, where the direction to the right is positive

x_f = -2 m

x₀ = +3 m

Δx = -2 -3

Δx = -5 m

we calculate

v = -5 / 10

v = -0.5 m / s

this value is a scalar