<h2>Answer </h2>
The kinetic energy is 8100 J.
<u>Explanation</u>
Mass is 50.0kg and velocity is 18 m/s, the kinetic energy is:
As we know the formula of kinetic energy which is K.E = ½ ( mv ^ 2 ),
mass = m = 50.0kg
velocity = v = 18 m / s,
by putting values in the formula,
K.E = ½ ( mv ^ 2 ),
K.E = ½ ( 50kg ) . ( 18 m / s ) ^ 2
K.E = ½ ( 50kg ) . ( 324 ),
=> K.E = 1/2 ( 16200 ),
=> K.E = 16200 / 2,
=> K.E = 8100J.
Hence, the kinetic energy ( K.E ) is 8100 joule ( J ).
Answer:
The frequency heard by the motorist is 4313.2 Hz.
Explanation:
let f1 be the frequency emited by the police car and f2 be the frequency heard by the motorist, let v1 be the speed of the police car and v2 be the speed of the motorist and v = 343 m/s be the speed of sound.
because the police car is moving towards the motorist at a higher speed, then the motorist will hear a increasing frequency and according to Dopper effect, that frequency is given by:
f1 = [(v + v2/(v - v1))]×(f2)
= [( 343 + 30)/(343 - 36)]×(3550)
= 4313.2 Hz
Therefore, the frequency heard by the motorist is 4313.2 Hz.
It confirmed medeleeve's hypothesis (prediction) and showed the use of his table
