A red car and a green car, identical except for the color, move toward each other in adjacent lanes and parallel to an x axis. At time t = 0, the red car is at xr = 0 and the green car is at xg = 220 m. If the red car has a constant velocity of +20 km/h, the cars pass each other at x = 45.5 m, and if it has a constant velocity of +40 km/h, they pass each other at x = 77.6 m.

Question

A red car and a green car, identical except for the color, move toward each other in adjacent lanes and parallel to an x axis. At time t = 0, the red car is at xr = 0 and the green car is at xg = 220 m. If the red car has a constant velocity of +20 km/h, the cars pass each other at x = 45.5 m, and if it has a constant velocity of +40 km/h, they pass each other at x = 77.6 m.

a.) What is the initial velocity of the green car?

b.)What is the acceleration of the green car?

Answer 1

To find the initial velocity of the green car, we need to use the formula for velocity:

velocity = displacement / time.

We have the displacement and time for both scenarios:

Scenario 1:
Displacement = 45.5 m
Time = 0

Scenario 2:
Displacement = 77.6 m
Time = 0

For scenario 1, the green car started at x = 220 m and ended at x = 45.5 m. The displacement is the difference between the final position (45.5 m) and the initial position (220 m). Thus:

Displacement = Final position - Initial position = 45.5 m - 220 m = -174.5 m

Using the formula mentioned above, we have:

Velocity = Displacement / Time
Initial velocity of the green car = -174.5 m / 0 = undefined

So we cannot determine the initial velocity of the green car in scenario 1.

For scenario 2, the green car started at x = 220 m and ended at x = 77.6 m. Again, the displacement is the difference between the final position (77.6 m) and the initial position (220 m). Thus:

Displacement = Final position - Initial position = 77.6 m - 220 m = -142.4 m

Using the formula mentioned above, we have:

Velocity = Displacement / Time
Initial velocity of the green car = -142.4 m / 0 = undefined

So we also cannot determine the initial velocity of the green car in scenario 2.

Therefore, the initial velocity of the green car cannot be determined based on the information given.

Moving on to part (b) - the acceleration of the green car.

Acceleration is the change in velocity divided by the time taken for that change. However, without knowing the initial or final velocity of the green car, we cannot determine its acceleration.

Thus, the acceleration of the green car cannot be determined based on the information given.