Answer:
a) The car was moving at a speed of 
b) The negative sign of
denotes that the observer is coming towards the police car which is the source of the sound.
c) 
Explanation:
Given:
- original frequency of the source,

- speed of the source,

- velocity of the obstacle car be,

- speed of sound,

- observed frequency,

<u>Using the equation from the Doppler's effect:</u>



a)
The car was moving at a speed of 
b)
The negative sign of
denotes that the observer is coming towards the police car which is the source of the sound.
c)
Now when, 
Then, 
Using the Doppler's eq.:


Answer:
Chemical energy to electrical energy to mechanical and thermal energy
Explanation:
In the rotating fan, the chemical energy stored in the battery is used to generate electrical energy.
The electrolytes within the battery undergoes chemical reactions that produces electric current.
- The current is being used to drive the motor of the fan to produce a mechanical energy as it rotates.
- In like manner, heat energy is also produced.
- So, energy is simply being transformed from one form to the other in this system.
Answer:
option C
Explanation:
Final velocity of the object is 114 m / s. Hence, final velocity of the object is 114 m / s.
The relationship between amperage, voltage, and power is that power equals the amperage quantity times the amount of voltage.
Power: is the amount of energy transferred or converted per unit time.
Answer:
m = B²qR² / 2 V
Explanation:
If v be the velocity after acceleration under potential difference of V
kinetic energy = loss of electric potential energy
1/2 m v² = Vq ,
v² = 2 Vq / m ----------------------- ( 1 )
In magnetic field , charged particle comes in circular motion in which magnetic force provides centripetal force
magnetic force = centripetal force
Bqv = mv² / R
v = BqR / m
v² = B²q²R² / m² ------------------------- (2)
from (1) and (2)
B²q²R² / m² = 2 Vq / m
m = B²q²R² / 2 Vq
m = B²qR² / 2 V