Ask a Teacher

Search



how can we find initial velocity and final velocity?
The three ways to calculate initial velocity
    1.Finding Initial Velocity with Final Velocity, Acceleration and Time
Equation used is v(i) = v(f) - a*t where 
v(i) - the initial velocity 
v(f) - the final velocity 
a  - the acceleration  and t - the time.

    2. Finding Initial Velocity with Distance, Time, and Acceleration
The necessary equation is: v(i) = (d / t) - [(a * t) / 2] where d stands for distance travelled.

    3. Finding Initial Velocity with Final Velocity, Acceleration and Distance
The correct equation is: v(i) = root [v(f) ^ 2 - (2 * a * d)]
The 1st and 3rd methods can be used to find final velocity when other components are given.
When average speed is known, average speed = 1/2 [ v(i) + v(f) ] .
When objects are dropped from different heights,the formula used to find final and initial velocity given only time and distance is 
1/2[v(f)]^2 - 1/2[v(i)]^2 = gH where
g is a constant = 9.8m/sec^2 (acceleration of gravity).
H is the height from which the object falls.


comments powered by Disqus