A Cambra pouce car traveling at 28 m/s slow
1 answer:
Answer:
t = 7.8 seconds
Explanation:
Given that,
The initial speed of the car, u = 28 m/s
Acceleration of the car, a = 3.6 m/s²
We need to find the time taken for the police car to come to Stop. When it stops, its final speed is equal to 0. So, using the equation of kinematics to find it i.e.
So, the required time is 7.8 seconds.
You might be interested in
The ball rolled for 13.2 s
<h3>Further explanation</h3>Speed is scalar and no direction
A bowling ball rolls 33 m, with average speed = 2.5 m/s
So elapsed time :
To solve this problem it is necessary to apply the concepts related to Dopler's Law. Dopler describes the change in frequency of a wave in relation to that of an observer who is in motion relative to the Source of the Wave.
It can be described as
c = Propagation speed of waves in the medium
= Speed of the receiver relative to the medium
= Speed of the source relative to the medium
Frequency emited by the source
The sign depends on whether the receiver or the source approach or move away from each other.
Our values are given by,
Velocity of car
velocity of motor
Velocity of sound
Frequency emited by the source
Replacing we have that
Therefore the frequency that hear the motorcyclist is 601.7Hz