A car is speeding up and has an instantaneous speed of 14.0 m/s when a stopwatch reads 9.0 s. It has a constant acceleration of 2.3 m/s2
(b) What is the speed when the stopwatch reads 12.2 s?
V = Vo + at,
V = 14 + 2.3(12.2-9) = 21.36m/s
To find the speed when the stopwatch reads 12.2 s, we can use the equation for the final speed (v) with constant acceleration (a) and time (t):
v = u + at
where:
v = final speed
u = initial speed
a = acceleration
t = time
Given:
Initial speed (u) = 14.0 m/s
Acceleration (a) = 2.3 m/s^2
Time (t) = 12.2 s
We can substitute the values into the equation and solve for the final speed (v):
v = 14.0 m/s + (2.3 m/s^2)(12.2 s)
v = 14.0 m/s + 28.06 m/s
v ≈ 42.06 m/s
Therefore, the speed when the stopwatch reads 12.2 s is approximately 42.06 m/s.
To find the speed of the car when the stopwatch reads 12.2 s, you can use the equation of motion:
V = V0 + a * t
Where:
V is the final velocity
V0 is the initial velocity
a is the constant acceleration
t is the time
In this case, the initial velocity (V0) is given as 14.0 m/s, the acceleration (a) is 2.3 m/s^2, and the time (t) is 12.2 s.
Substituting the values into the equation:
V = 14.0 m/s + 2.3 m/s^2 * 12.2 s
Now, multiply the acceleration (2.3 m/s^2) by the time (12.2 s):
V = 14.0 m/s + 28.06 m/s
Finally, add the initial velocity (14.0 m/s) and the product of acceleration and time (28.06 m/s):
V = 14.0 m/s + 28.06 m/s
Simplifying the expression, the speed of the car when the stopwatch reads 12.2 s is:
V = 42.06 m/s