Answer:
Explanation:
Solution:
- We are to develop a circuit that has an input of available battery 9.0 V and has an output potential difference of 3.0 V
- We are given:
Battery ..... 9.0 V
Resistors ... 10 Kohms
- We will develop a potential divider circuit by placing a few resistors in series and then connecting in between resistors to get our desired voltage.
- How many resistors should we use ?
We know that if we add series resistance in a circuit the current decreases proportionally. However, the potential difference across resistors also changes.
- Our desired voltage is a ratio of input battery voltage.
Input / Output = 9 / 3 = 3
We can use this ratio as the number of "Identical resistors" that can be placed in series to give us the desired voltage. Note: This would not be true if we did not had any identical resistors.
- We will place 3, 10 Kohms resistors in series.
- To verify we will calculate the potential difference across each resistor. The current of the total circuit is:
I = V / R_eq
R_eq = 3*R = 30 kohms
I = 9 / 30,000 = 0.0003 Amps
- Now the potential difference for each resistor:
V = I*R_each
V = 0.0003*(10,000)
V = 3.0 V
- We can take two leads across any 10 kohms resistor and the potential difference across the leads would be the desired voltage 3.0 V.
<span>So we want to know what will happen when the fast moving car that is making loud noise that is initially approaching the person, passes the person and starts to move away. So Doppler effect is a phenomenon where when the source of a sound is approaching a person, the person hears the sound as higher than if the source was standing still with respect to the person because the wavelength is getting shorter, and as the source is moving avay from the person the sound is getting deeper because the wavelength is getting longer. So the correct answer is A. </span>
Answer
graph 2
Explanation
Velocity is the rate of change of displacement.
Velocity = (change in displacement)/(change is time)
In graph 2, the gradient of the curve is positive, indicating that the velocity is positive.
Acceleration is the rate of change of velocity.
The steepness of the slope of the same graph (graph 2) is decreasing. This shows that the velocity is decreasing hence a negative acceleration.
