Calculating Velocity Without Time Factor | Physics Homework

In summary, the person is trying to create a physics problem for their class but is missing the time factor in the equation v=d/t. They have the necessary information such as velocity, distance, mass, density, volume, and area, but are unsure of how to calculate the time it would take for an object to fall a certain distance. They are also looking for a way to find drag and q without knowing velocity. The problem will involve solving for multiple unknowns including drag and terminal velocity. The person suggests using the equation x=v-initial*t+1/2*a*t^2 for an object falling from rest, and mentions the acceleration due to gravity as 938m/s^2. They also ask if there is a way to
  • #1
Sesquipedalian
3
0
I am just getting into physics and I have met a problem, I have almost all of the information I need to make a problem for other students in my class but the problem is I do not have the time factor in v=d/t is there any other way that I am able to calculate for Velocity?
 
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  • #2
dx/dt

Velocity is the time derivative of the inital position function x(t). You need time. Perhaps your time value is meant to be a variable. It would help if you descrbed your problem a little more



EDIT:
If you are given the directional velocities(D.V.) i.e velocities in the x, y, and z directions, you can find the overall velocity by adding the squares of the D.V. and taking the squareroot
 
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  • #3
Do you have accelleration?
 
  • #4
I don't think I was fully clear, I am trying to make a problem for fellow students in my class (I'm in 7th Grade). For my problem I don't have an acceleration because I am trying to make up the whole thing from (almost) scratch. What I have is the Drag Coefficient, Distance, Mass, Density, Volume, and Area. What I am trying to do is calculate the time it would take to fall an x amount of distance then make it into a problem using everything. And in the end it will ask them to calculate for Drag and Terminal Velocity. The problem really won't be very complicated, but the only thing I still need is velocity, so I can solve for q in Drag=mg-qv^2.

I guess what I should be asking is if there is a different way to find time besides t=d/v because if I had the velocity wouldn't I know the time in the first place? Or maybe is there a different way to find Drag and q without knowing Velocity?

EDIT: Problem will be somewhat like a problem with a lot of unknowns but they can be found easily..

A 20x10x5 brick with a volume of a, a density of b, and a mass of 2.27kg is falling from a height of c, the time it takes for it to fall that distance is (?) when the velocity=(?), the Drag Coefficient of this brick is 2.1. With that information solve for each of the unknowns and then solve for Drag and Terminal Velocity whereas Drag=mg-qv^2 and where q=1/2ρCdA. Vt(Terminal Velocity)=squareroot(2mg/CdρA).

The (?)'s are the things I don't know yet.
 
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  • #5
Is it falling from rest? If so, they can use

x=v-initial *t +1/2*a*t^2

And if it's falling, you do have an acceleration, g.
 
  • #6
You mean the acceleration due to gravity, 938m/s^2?

And its just being dropped, to find the velocity will I have to a website that has done this with a falling brick and calculated its velocity by experiments, or is there a different way I could be able to find what t is equal to?
 

Related to Calculating Velocity Without Time Factor | Physics Homework

1. How do I calculate velocity without knowing the time?

To calculate velocity without knowing the time, you can use the equation v = d/t, where v represents velocity, d represents distance, and t represents time. Rearrange the equation to solve for time, t = d/v. This will give you the time it takes to travel a certain distance at a given velocity.

2. Can I use a different equation to calculate velocity without time?

Yes, there are other equations that can be used to calculate velocity without knowing the time. For example, if you know the initial velocity (u), final velocity (v), and acceleration (a) of an object, you can use the equation v^2 = u^2 + 2ad to find the final velocity. From there, you can use the same equation v = d/t to calculate the time.

3. Is it possible to calculate velocity without time in real-world situations?

Yes, it is possible to calculate velocity without time in real-world situations. For example, if you know the distance traveled and the change in velocity of a car during a certain time interval, you can use the equation v = (v1 + v2)/2 to find the average velocity of the car during that time period.

4. Can velocity be negative when calculating without time?

Yes, velocity can be negative when calculating without time. This occurs when the direction of motion is in the opposite direction of the positive direction. For example, if an object is traveling west and the positive direction is east, the velocity would be negative.

5. How does calculating velocity without time factor into other concepts in physics?

Calculating velocity without time is an important concept in kinematics, the branch of physics that deals with motion. It is also related to other concepts such as acceleration, displacement, and distance. Understanding how to calculate velocity without time is crucial in solving various physics problems involving motion.

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