Answer:
The smallest microwave frequency is 1.5 GHz.
Explanation:
Given that,
Distance d= 20 cm
We need to calculate the wavelength
Using formula for maximum diffraction
For maximum, 
We need to calculate the frequency
Hence, The smallest microwave frequency is 1.5 GHz.
Answer:
47.415 km .
Explanation:
We are given;
- Time taken is 1.45 hours
- Average speed of the bicycle is 32.7 Km/hr
We are supposed to work out for the distance;
- We know that speed is the rate of change in distance given by;
Rearranging the formula, we can get distance;
Distance = Speed × time
In this case;
Distance = 32.7 km/hr × 1.45 hours
= 47.415 km .
Thus, the bicyclist travels for a distance of 47.415 km at the average speed of 32.7 km/hr.
Answer:
i) Q' = Q/2.
ii) If the wires to the battery are disconnected, the amount of charge on the plates remains constant, and the voltage across the plates remains the same.
Explanation:
i) The formula for capacitance is given as
C = A/d
Where d = separation between the plates
The formula for the charge stored is given as
Q = CV
Q = AV/d
When "d" is doubled, the charge stored "Q" becomes half because Q is inversely proportional to the separation between the plates, d.
Thus, Q' = Q/2.
ii) If the wires to the battery are disconnected, the amount of charge on the plates remains constant, and the voltage across the plates remains the same.
Answer:
5*10^25 atoms of carbon
Explanation:
<u>Check from the periodic table:</u>
M(carbon) = 12.01 g/mol
<u>Convert kg into g:</u>
1 kg = 1000 g
<u>Calculate the number of moles of carbon:</u>
n(carbon) = (1000 g) ÷ (12.01 g/mol) = 83.26 mol
<u>Convert moles into number of particles:</u>
#(carbon) = n × NA = 83.26 mol × 6*10^23
= 5*10^25 particles
<em>N</em><em>o</em><em>t</em><em>e</em><em>:</em><em> </em><em>NA represents the Avogadro's Number, which has the value 6.02*10^23 particles/mol</em><em>.</em>
The ideal concept for solving this question is based on the Doppler effect, for which it is indicated that the source's listening frequency changes as the distance and the relative speed between the receiver and the transmitter are also changed. However, if the relative velocity between the two objects is zero as in the particular case presented (since both travel at 75km / h) we have that there will be no change in frequency.
Therefore the frequency that I hear and that my sister would listen would be the same.
