Answer: relative motion between observer and the sound source.
Explanation: The Doppler effect states that when there is a relative motion between an observer and a sound source the frequency of sound perceived by the observer is different in frequency from the original from the source.
The mathematical back up for this claim is given below.
f' = (v+v') /(v-vs) × f
Where f' = observed frequency
v = speed of sound in air
v' = velocity of observer
vs = velocity of source
f = frequency of sound source.
From the formulae, it can be seen that a change in the value of the velocity of observer (v') and source (vs) produces different value of observed frequency (f').
Note, frequency of sound (f) is a constant.
The correct answer is D. The movement of the molecules will gradually increase.
Explanation:
At the beginning of the model the state of matter of the water is solid, in this, particles have a defined arrangement and are together, which stops particles from moving freely and only allows them to vibrate. However, as the substance is heated the thermal energy (heat) increases in the sample, this causes particles to move more and the arrangement of it changes. Due to this, when the ice melts and there is liquid water particles move more than in solid states, which makes ice lacks a defined shape. Moreover, as the heat continues to increase the thermal and kinetic energy (movement) increases, indeed in gas state (water vapor) particles will move freely. This means the movement or kinetic energy in particles gradually increases in the model.
Then the object moves in a circle.
Answer:
D. 3.0 m/s
Explanation:
because I did this in my class
Answer:
The kinetic energy increases 4 times
Explanation:
Given,
The mass of the car, m = 1500 Kg
The speed of the car doubles from 50 Km/h to 100 Km/h
The kinetic energy at 50 Km/h
K.E = ½mv²
= ½ x 1500 x 50²
= 1875000 J
The kinetic energy of the car at 100 Km/h
K.E = ½mv²
= ½ x 1500 x 100²
= 7500000 J
Hence, the final K.E is 4 times the initial K.E
