Answer:
Wave X has a shorter wavelength.
Explanation:
The relation between the speed of a wave, its wavelength and frequency is given by :
It can be seen that the relationship between the frequency and wavelength is inverse.
In this problem, it is mentioned that two sound waves (wave X and wave Y) are moving through a medium at the same speed. The frequency of wave X is greater than wave Y. Then it would mean that wave X have shorter wavelength than wave Y (due to inverse relation).
Answer:
The reactance of the capacitor
Explanation:
In an AC circuit containing different elements (capacitors, resistors and inductors), we cannot simply calculate the equivalent resistance of the circuit, so another quantity is used, which is called reactance.
For a capacitor, the reactance is given by:
where:
f is the frequency of the AC current in the circuit
C is the capacitance of the capacitor
The reactance has a similar meaning to that of the resistance for a DC current. In fact, we notice that:
- When f=0 (which means we are in regime of DC current, because the current never changes direction), the reactance is infinite. This is correct: in a DC circuit, the capacitor does not let current pass through it, so it like it has infinite resistance (=infinite reactance)
- When f tends to infinite, the reactance becomes zero: in such situation, the current in the circuit changes direction so quickly that the capacitor has no enough time to "block" the current in the circuit, so it like it has almost zero resistance (zero reactance).