when a break are applied to moving car travelling at 6kmh-1 it decelerate at uniform rate as 5ms2.calculate the time taken to reach the velocity 36kmh-1
Usman Bello moriki
change km/hr to m/s
then vf=vi+at
time= (vf-vi)/a solve for time taken
To calculate the time taken to reach a certain velocity, we can use the formula for uniform acceleration:
V = U + at
Where:
V is the final velocity
U is the initial velocity
a is the acceleration
t is the time
In this case, the car is initially traveling at 6 km/h, which needs to be converted to m/s. We know that 1 km/h is equal to 0.27778 m/s.
So the initial velocity U = 6 km/h * 0.27778 m/s = 1.667 m/s.
The final velocity V = 36 km/h * 0.27778 m/s = 10 m/s.
The acceleration in this case, since it's decelerating, is a negative value. Given that the deceleration is uniform at 5 m/s², the acceleration a = -5 m/s².
Now, we can rearrange the formula:
V = U + at
t = (V - U) / a
Substituting the values:
t = (10 m/s - 1.667 m/s) / -5 m/s²
t = (8.333 m/s) / -5 m/s²
t ≈ -1.67 s
Since time cannot be negative, we ignore the negative sign. Therefore, the time taken to reach a velocity of 36 km/h is approximately 1.67 seconds.