Can anyone confirm that the equation for velocity AT A PARTICULAR POINT (not average velocity) is velocity=distance/time? (v=d/t)

Because when i use it, the answers im getting are drastically lower than expected... but seem to be consistantly low. this is making me think that ive left out a factor somewhere


It could also be something wrong with the distance measurements i have, but i just wanted to double-check that my equation is right


All help appriciated

The basic equation is distance = speed * time.
So speed = distance/time. This does give the average speed.
To work out the speed at a given point you need to know the initial speed, the acceleration and the time elapsed. This is only applicable in a constant acceleration system.
These are gathered in the equation:

v = u + a*t where u is initial velocity, a acceleration and t time.

Check the thread at the top of the board for explanation of such ideas.

You also have to make sure you are keeping the units constant. If your question states that an object is has travelled some number of miles in some amount of seconds and asks what the velocity in MPH is you must recognize that there are 3600 seconds in an hour and convert the value of seconds into hours first.(or similarily if it has moved a number of feet while asking for the MPH then you must convert feet into miles with 5280 feet = mile )

Average v is defined at d/t. However, v at a particular point is a simple differentiation problem. If given an equation for position as a function of time, simply take the derivative of that function with respect to time. If the velocity is not constant, then the derivative should involve a variable. Plug in the time for which you wish to know the velocity and solve. That's all there is to it.

I hope you have some experience with calculus, else this is likely of little use to you. Contact me with any additional questions.

This might sound really stupid but does anyone know the answer to this question because i am really confused:

A car is moving along a road at 10m/s. When it leaves the town, it speeds up. After 8s it is moving at 22m/s.

What is the cars average speed during the time it is accelerating?

would you use the formula u+a*t to get 186? i have no idea- please help

To arrive at average speed add the initial speed to the final speed and divide by 2.

thank you very much