Answer:
887.1Hz
Explanation:
Given parameters:
Speed of sound wave = 330m/s
Wavelength = 0.372m
Unknown:
Frequency = ?
Solution:
To solve this problem, we use the expression below:
Speed = Frequency x wavelength
330 = Frequency x 0.372
Frequency = 887.1Hz
Answer:
The applied torque is 3.84 N-m.
Explanation:
Given that,
Moment of inertia of the wheel is 
Initial speed of the wheel is 0 (at rest)
Final angular speed is 25 rad/s
Time, t = 13 s
The relation between moment of inertia and torque is given by :

So, the applied torque is 3.84 N-m.
Answer:
20.60 kV
Explanation:
Capacitance of parallel plates without dielectric between them is:

with d the distance between the plates, A the area of the plates and ε₀ the constant
, so :

But the dielectric constant is defined as:

With C the effective capacitance (with the dielectric) and Co the original capacitance (without the dielectric). So, the new capacitance is:

But capacitance is related with voltage by:

with Q the charge and V the voltage, using the new capacitance and solving for V:


Answer:
the second time there is a gas between you and the star,
Explanation:
When you observe the star for the first time you do not have a given between you and the star, therefore you observe the emission spectrum of the same that is formed by lines of different intensity and position that indicate the type and percentage of the atoms that make up the star.
When you observe the same phenomenon for the second time there is a gas between you and the star, this gas absorbs the wavelengths of the star that has the same energies and the atomisms and molecular gas, therefore these lines are not observed by seeing a series of dark bands,
The information obtained from the two spectra is the same, the type of atoms that make up the star