# Distance vs. Total distance

• January 5th 2009, 02:20 PM
CalcGeek31
Distance vs. Total distance
Hi, I am working on some acceleration, velocity, and position problems and I wanted to know the difference between distance and total distance. Any guidance would be helpful.
• January 5th 2009, 02:25 PM
craig
The way I got tought it is the following.

Say a particle moves from the starting point upwards to a point 10 metres above the ground, then falls back to the starting position.

The total distance the particle has moved is of course 20 metres, but the displacement (distance moved from starting point) is 0.

Sorry if this is not what you meant :)
• January 5th 2009, 02:30 PM
CalcGeek31
That is what Im looking for but in a hint that are teacher gave, she told us that displacement was total distance. I am not sure it that is right but I think she stated it wrongly. Correct me if I am wrong
• January 5th 2009, 02:32 PM
craig
Could she have said that displacement is total distance traveled from the starting point or something like that?

Sounds a bit ambiguous what she has said ;)
• January 5th 2009, 03:35 PM
mr fantastic
Quote:

Originally Posted by CalcGeek31
That is what Im looking for but in a hint that are teacher gave, she told us that displacement was total distance. I am not sure it that is right but I think she stated it wrongly. Correct me if I am wrong

The statement "displacement was total distance" is totally wrong.

Consider a particle that moves 4 units right and then 4 units left. Displacement = 0 units, distance = 8 units ....

The difference between displacement and total distance (from which all other differences come from) is that displacement is a vector and distance is a scalar.
• January 5th 2009, 04:22 PM
skeeter
distance traveled $\geq$ displacement

equality between the two occurs only if velocity is positive and there is no change in direction