# Instantaneous versus average velocity?

#### DeltaForce

Gold Member
Homework Statement
If the instantaneous velocity does not change, will the average velocities for different time intervals differ?
Homework Equations
avg velocity
instantaneous velocity
I have a hard time understanding what this problem even means. So I can't even begin with it.

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#### hutchphd

Homework Statement: If the instantaneous velocity does not change, will the average velocities for different time intervals differ?
Homework Equations: avg velocity
instantaneous velocity

I have a hard time understanding what this problem even means. So I can't even begin with it.
Maybe I understand. Define for me the average velocity and the instantaneous velocity. How do they differ.?

#### haruspex

Homework Helper
Gold Member
2018 Award
Homework Statement: If the instantaneous velocity does not change, will the average velocities for different time intervals differ?
Homework Equations: avg velocity
instantaneous velocity

I have a hard time understanding what this problem even means. So I can't even begin with it.
The instantaneous velocity not changing just means the velocity is constant.
If in time interval (t,t+Δt) the position vector changes from $\vec x$ to $\vec x+\vec{\Delta x}$ then the average velocity over that time interval is $\frac{\vec{\Delta x}}{\Delta t}$.

#### archaic

basically, if $\frac {d\vec {x}}{dt}$ is the same at every moment during the movement, then would you get a different average velocity if you compute it for different time intervals, say between $t_1$ and $t_2$ and between $t_3$ and $t_4$.

"Instantaneous versus average velocity?"

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