I need help on this problem

Question

1. A roller-coaster rider traveling in a straight line changes from a speed of 4 m/s to 16 m/s in 3 s. Calculate the acceleration of the ride.
2. Identify the following situations as an example of either distance, displacement, speed, velocity, or acceleration.

a) a car traveling at 50 km/h

b) a student riding a bike at 4 m/s toward home

c) a roller-coaster ride whips around a left turn at 5 m/s

d) a roller-coaster car is dragged up a hill 12 m tall traveling at 3 m/s.

e) a train ride takes you 150 km northwest

Answer 1

I'll try to answer without just solving the problems:

1) Acceleration is the rate of change of velocity per unit time, which you can write as Δv / t

1. Time is given
2. Δv can be found by subtracting the initial speed from the final speed.

2)

1. Distances and displacements are given in units like miles, meters, kilometers, etc. The only difference is that displacement has a direction with it, but distance does not.
2. Velocity and speed use units like m/s, km/hr, mi/hr, etc. -- the only difference again is that velocity has a direction with it, while speed does not.
3. Acceleration involves a change in speed OR direction. So, if a car is driving in circles, it is accelerating even if it stays at the same speed (technically, its velocity is changing). It is usually in units of m/s², ft/s², etc.