How Do You Calculate Final Velocity with Uniform Acceleration?

In summary, the conversation is about determining the acceleration of an object with an initial velocity of 24 cm/s and uniformly accelerating through a distance of 66 cm in 3.8 seconds. The equations discussed to find acceleration are Vf = Vi + at, Delta x = .5(vf+vi)t, Delta x = Vi(t)+.5a(t^2), and Vf^2 = Vi^2 + 2a(delta x). The final velocity was found to be 10.737 m/s and the object was determined to be slowing down. The next step is to use the given information to calculate the acceleration.
  • #1
BuhRock
33
0
1. Determine the acceleration of an object whose velocity is initially 24 cm/s and which accelerates uniformly through a distance of 66 cm in 3.8 seconds.




2. s = (vf + v0) / 2 * t,



3. I tried rearranging that formula but I got vf= 477.6. This just doesn't make any sense
 
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  • #2
BuhRock said:
1. Determine the acceleration of an object whose velocity is initially 24 cm/s and which accelerates uniformly through a distance of 66 cm in 3.8 seconds.




2. s = (vf + v0) / 2 * t,



3. I tried rearranging that formula but I got vf= 477.6. This just doesn't make any sense

Didnt you just find the final velocity? they asked for acceleration, so you should be solving for that since you have the time. you can find out the acceleration
 
  • #3
I was saying that the vf being 477.6 doesn't make sense. Also, how can I find a with just t.
 
  • #4
BuhRock said:
I was saying that the vf being 477.6 doesn't make sense. Also, how can I find a with just t.
Determine the kinematic equation that you would have to use...

Vf = Vi + at
Delta x = .5(vf+vi)t
Delta x = Vi(t)+.5a(t^2)
Vf^2 = Vi^2 + 2a(delta x)

Choose which one you would use, and solve for Vf.
 
  • #5
BuhRock said:
2. s = (vf + v0) / 2 * t,



3. I tried rearranging that formula but I got vf= 477.6. This just doesn't make any sense
You apparently interpreted the equation as being s = (vf + v0) / (2 * t)

However the equation is equivalent to s = ((vf + v0) / 2) * t
 
  • #6
With uniform acceleration, can you say that average velocity * 2 = vf?

Aggression200 said:
Determine the kinematic equation that you would have to use...

Vf = Vi + at
Delta x = .5(vf+vi)t
Delta x = Vi(t)+.5a(t^2)
Vf^2 = Vi^2 + 2a(delta x)

Choose which one you would use, and solve for Vf.

Well I don't have acceleration. I was thinking I would use the second one, but I don't have vf. What is delta x?
 
Last edited:
  • #7
You can find average velocity. From that and the initial velocity you can find final velocity. Then acceleration.
 
  • #8
I tried taking the equation s = .5(vo+vf)t and rearranging it to get vf, which got me 10.7 which can't be right. What is the delta x in those equations?

I have initial velocity, which is 24 m/s. I have average velocity which is 17.36(Displacement / time). So, from here. What do I use?
 
  • #9
vf = 10.737 m/s is about right.

The initial velocity is greater than the average velocity, so the object is slowing down.

Now find the acceleration.
 

Related to How Do You Calculate Final Velocity with Uniform Acceleration?

1. What is the formula for finding final velocity?

The formula for finding final velocity is Vf = Vi + at, where Vf is the final velocity, Vi is the initial velocity, a is the acceleration, and t is the time.

2. How do you calculate final velocity?

To calculate final velocity, you need to know the initial velocity, acceleration, and time. You can use the formula Vf = Vi + at to find the final velocity.

3. What is the difference between final velocity and initial velocity?

Final velocity is the velocity of an object at the end of a given time while initial velocity is the velocity of an object at the beginning of a given time. Final velocity takes into account the acceleration of the object, while initial velocity does not.

4. Can final velocity be negative?

Yes, final velocity can be negative. A negative final velocity indicates that the object is moving in the opposite direction of its initial velocity. This is often seen in cases of deceleration or slowing down.

5. What units are used to measure final velocity?

Final velocity is typically measured in units of distance per time, such as meters per second (m/s) or kilometers per hour (km/h). The specific unit used will depend on the units of the initial velocity, acceleration, and time in the given problem.

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