Why do the units for time appear twice in the units for acceleration

[mppaki]

1. why do the units for time appear twice in the units for acceleration
2. a = v/t - v1-vo/t1-t0
3. once for speed change and once for time change.

1. what is the acceleration of a car that travels in a straight line at a constant speed of 27 m/s?
2. 27m/s / 10s
3. 2.7m

 

[AEM]

1. why do the units for time appear twice in the units for acceleration
2. a = v/t - v1-vo/t1-t0
3. once for speed change and once for time change.

1. what is the acceleration of a car that travels in a straight line at a constant speed of 27 m/s?
2. 27m/s / 10s
3. 2.7m

Is this:

1. why do the units for time appear twice in the units for acceleration

your first question?

Is this:

2. a = v/t - v1-vo/t1-t0

a possible answer?

It's not clear what you would like help with. Identify your question, then show your attempt to answer it.

 

[mppaki]

a = v/t = v1-v0/t1-t0

i just want to know if i got the right answer or not

 

[glueball8]

a = v/t = v1-v0/t1-t0

i just want to know if i got the right answer or not

a=\frac{\Delta v}{\Delta t}= \frac{v_{f}-v_{o}}{t_{f}-t_{o}}

you can't write it like "v1-v0/t1-t0" this means that v1 minus (vo over t1) minus t0.

 

[mppaki]

a=\frac{\Delta v}{\Delta t}= \frac{v_{f}-v_{o}}{t_{f}-t_{o}}

you can't write it like "v1-v0/t1-t0" this means that v1 minus (vo over t1) minus t0.

yeah that's the equation i thought would relate, but are my answer correct?

 

[glueball8]

What exactly is your question?

 

[mppaki]

both number 1

 

[AEM]

1. why do the units for time appear twice in the units for acceleration
2. a = v/t - v1-vo/t1-t0
3. once for speed change and once for time change.

1. what is the acceleration of a car that travels in a straight line at a constant speed of 27 m/s?
2. 27m/s / 10s
3. 2.7m

Okay, now that you have told us that Number 1 is the question in both cases, we can help you. First, your answer to question 1 is not correct. Think about the definitions. Velocity is change in position divided by change in time so the units are length/time or

V = \frac{L}{T}

Now acceleration is change in velocity divided by time. Take the equation I just wrote and do the algebra. What do you see?

For the second question. What is the adjective modifying the word speed? What is the definition of velocity that I just wrote? Put those tow ideas together and what do you get?

Hint: With physics sometime it's useful to ask "What does it mean?" and then go back and look at the definitions.