To develop this problem it is necessary to apply the concept of Frequency based on speed and wavelength.
According to the definition the frequency can be expressed as

Where,
v = Velocity
Wavelength
Our value are given by,
v = 345m/s

Replacing


Therefore the frequency of the tuning fork is 547.61Hz
Answer:
Option b. is correct
Explanation:
An RLC electrical circuit consists of constituent components: a resistor (R), an inductor (L), and a capacitor (C). A resistor, an inductor, and a capacitor are connected in series or parallel.
The impedances of the circuit elements depend on the frequency.
Both impedance magnitudes decrease when the frequency increases
Answer:
4,200 joules per kilogram per degree Celsius
Explanation:
The specific heat capacity of a material is the energy required to raise one kilogram (kg) of the material by one degree Celsius (°C). The specific heat capacity of water is 4,200 joules per kilogram per degree Celsius (J/kg°C). This means that it takes 4,200 J to raise the temperature of 1 kg of water by 1°C.
Answer:
velocity during second d = 20.0 mi/h
Explanation:
Total distance travelled is 2d, with an average velocity of 30.0 mi/h you can express the time travelled in terms of d:
distance = velocity * time
time = distance / velocity
time = 2d/30.0
The time needed for the first d at 60.0 is:
time = d/60.0
The time in the second d you can get it by substracting both times (total time - time for the first d)
second d time = 2d/30.0 - d/60.0
= 4d/60.0 - d/60.0
= 3d/60.0
and with the time (3d/60.0) and the distance travelled (d) you can get the velocity:
velocity = distance / time
velocity = d / (3d/60.0)
= 60.0/3 = 20.0 mi/h