Acceleration Notes

Acceleration

  • Acceleration depends on:

    • Initial velocity
    • Final velocity
    • Time interval over which velocity changes
  • Equation:

    • acceleration=ΔVΔTacceleration = {\Delta V \over \Delta T}
    • Where ΔV\Delta V is the change in velocity and ΔT\Delta T is the change in time.
  • Delta V:

    • ΔV=FinalVelocityInitialVelocity{\Delta V} = Final Velocity - Initial Velocity
  • Delta T:

    • ΔT=FinalTimeInitialTime{\Delta T} = Final Time - Initial Time
    • Often the delta is left off of time because time cannot be negative.
  • Units for Acceleration:

    • Meters per second squared (m/s2m/s^2).
    • This means the velocity is changing x meters per second each second that passes.

Example Problem: Race Car Acceleration

  • Problem: A race car moving west speeds up from 17 m/s to 47 m/s in 2 seconds. What is the car's acceleration?

  • Given Information:

    • Initial Velocity (ViV_i) = 17 m/s
    • Final Velocity (VfV_f) = 47 m/s
    • Time (t) = 2 seconds
  • Solution:

    • Using the formula: acceleration=ΔVΔTacceleration = {\Delta V \over \Delta T}
    • Plugging in the values: acceleration=47m/s17m/s2sacceleration = {{47 m/s - 17 m/s} \over {2 s}}
    • Calculating: acceleration=30m/s2sacceleration = {{30 m/s} \over {2 s}}
    • Final Answer: acceleration=15m/s2acceleration = 15 m/s^2
    • The car is accelerating at 15 meters per second squared.