when the moving brakes are applied to a moving car travelling at 60km/h, it discelerates at a uniform rate at 5m/s. calculate the time taken to reach the velocity of 36km/hr.
Vo = 60km/h = 60,000m/3600s = 16.7 m/s.
V = 36km/h = 36,000m/3600s = 10 m/s.
V = Vo + a*t = 10.
16.7 + (-5)t = 10,
T =
To calculate the time taken to reach a velocity of 36 km/hr, we need to first convert the velocities to the same unit. Since we are given the initial velocity as 60 km/hr and the final velocity as 36 km/hr, we can convert these values to m/s.
1 km/hr is equivalent to (1000/3600) m/s, so:
Initial Velocity: 60 km/hr * (1000/3600) m/s
= 16.67 m/s
Final Velocity: 36 km/hr * (1000/3600) m/s
= 10 m/s
Now that we have the initial velocity (u), final velocity (v), and the uniform rate of deceleration (a), we can use the equation of motion to find the time (t) taken.
The equation of motion in this case is:
v = u + at
Rearranging the equation to solve for time (t):
t = (v - u) / a
Plugging in the values:
t = (10 m/s - 16.67 m/s) / -5 m/s^2
Simplifying the equation:
t = (-6.67 m/s) / (-5 m/s^2)
t ≈ 1.34 seconds
Therefore, the time taken for the car to reach a velocity of 36 km/hr (10 m/s) is approximately 1.34 seconds.