Answer:
3 mA.
Explanation:
The following data were obtained from the question:
Resistor (R) = 500 Ω
Potential difference (V) = 1.5 V
Current (I) =.?
Using the ohm's law equation, we can obtain the current as follow:
V = IR
1.5 = I x 500
Divide both side by 500
I = 1.5 / 500
I = 3×10¯³ A.
Therefore, the current in the circuit is 3×10¯³ A.
Finally, we shall convert 3×10¯³ A to milliampere (mA).
This can be obtained as follow:
Recall:
1 A = 1000 mA
Therefore,
3×10¯³ A = 3×10¯³ × 1000 = 3 mA
Therefore, 3×10¯³ A is equivalent to 3 mA.
Thus, the current in mA flowing through the circuit is 3 mA.
Answer:
m' = 1 x 10⁻⁶ kg/s
Explanation:
Given that
Diffussion constant = 1 x 10⁻¹¹
Mass flow rate ,m = 2 x 10⁻⁶ kg/s
The diffusion is inversely proportional to the thickness of the membrane and therefore when the thickness is doubled, the mass flow rate would become half.
So new flow rate m'


m' = 1 x 10⁻⁶ kg/s
Answer:
a) 
b) 
c) 
d) 
Explanation:
Given:
- velocity of the sound from the source,

- original frequency of sound from the source,

- speed of the source,

(a)
We know time period is inverse of frequency:
Mathematically:



(b)
Distance travelled by the motorcycle during one period of sound oscillation:



(c)
The distance travelled by the sound during the period of one oscillation is its wavelength.



(d)
observer frequency with respect to a stationary observer:
<u>According to the Doppler's effect:</u>
...........................(1)
where:
are the observed frequency and the velocity of observer respectively.
Here, observer is stationary.

Now, putting values in eq. (1)


Answer:
percent decrease in power = 20 % .
Explanation:
Power P = v² / R where v is voltage and R is resistance which is constant .
taking log on both sides
log P = 2 log v - log R
differentiating on both sides
dP/P = 2 dv/v
-dP/P x 100 = 2 x -dv/v x 100
percent decrease in power = 2 x percent decrease in v ( voltage )
percent decrease in power = 2 x 10 = 20 %