Information that is given:
a = -5.4m/s^2
v0 = 25 m/s
---------------------
S = ?
Calculate the S(distance car traveled) with the formula for velocity of decelerated motion:
v^2 = v0^2 - 2aS
The velocity at the end of the motion equals zero (0) because the car stops, so v=0.
0 = v0^2 - 2aS
v0^2 = 2aS
S = v0^2/2a
S = (25 m/s)^2/(2×5.4 m/s^2)
S = (25 m/s)^2/(10.8 m/s^2)
S = (625 m^2/s^2)/(10.8 m/s^2)
S = 57.87 m
The answers is
D. The acid creates cracks in the rocks, which
allow air to circulate through the rock,
causing it to weather
It means that velocity not only has a size, but it also has a direction.
Some other vector quantities are force and acceleration.
They have sizes and directions.
Temperature, cost, and weight are quantities with only size and no direction.
Those are called "scalar" quantities.