the velocity of a body moving with uniform acceleration is 10m/s at a particular instant. its velocity after 5 sec is 20m/s. what was the velocity of the body 3 sec before that instant?
a=(vf-vi)/time=(20-10)/5=2m/s^2
v(t)=vi+a(t)
v(-3)=10+2(-3)=4m/s
To find the velocity of the body 3 seconds before the given instant, we need to use the equations of motion. Let's denote the initial velocity as u, the final velocity as v, the time taken as t, and the acceleration as a.
We are given the following information:
Initial velocity (u) = 10 m/s
Time after which velocity is 20 m/s (t) = 5 seconds
Final velocity (v) = 20 m/s
We can use the equation of motion that relates initial velocity, final velocity, acceleration, and time:
v = u + at
Rearranging the equation to isolate acceleration (a), we get:
a = (v - u) / t
Substituting the given values, we have:
a = (20 - 10) / 5
a = 10 / 5
a = 2 m/s²
Now, we can find the initial velocity (u) by using the equation of motion:
v = u + at
Rearranging the equation to isolate initial velocity (u), we get:
u = v - at
Substituting the known values, we have:
u = 20 - 2 * 5
u = 20 - 10
u = 10 m/s
Therefore, the velocity of the body 3 seconds before the given instant was 10 m/s.