To begin with, we can use the formula that links frequency, wavelength and velocity.
Because you already have the wavelength and the frequency, you just need to solve for velocity. You can do this by multiplying each side of the equation by frequency.
Therefore, 400 x 2.5 = 1000m/s.
Hope this helps :)
Answer with Explanation:
We are given that
Length of wire 1=
Length of wire 2=
Resistivity of copper wire=
Resistivity of aluminum wire=
Wire 1=Copper wire
Wire 2=Aluminum wire
Diameter of both wires are same and resistance of both wires are also same.
We know that
Resistance =
When diameter of wires are same then their cross section area are also same .

When resistance and area are same then the length of wire depend upon the resistivity of wire .
The length of wire is inversely proportional to resistivity.
When resistivity is greater then the length of wire will be short and when the resistivity is small then the length of wire will be large.

Therefore, 
Hence, the length of wire 1 (copper wire) is greater than the length of wire 2 (aluminum).


The factors that can cause an induced current in a wire loop are number of turns of the wire, area of the wire and magnetic field strength.
<h3>
Induced emf</h3>
According to Faraday's law of electromagnetic induction, the rate of change of flux in a magnetic field is proportional to the flux through the magnetic field.
emf = dФ/dt
where;
- Ф is magnetic flux = BA (magnetic field and area of the coil)
emf = N(BA)/dt
where;
Thus, the factors that can cause an induced current in a wire loop are number of turns of the wire, area of the wire and magnetic field strength.
Learn more about electromagnetic induction here: brainly.com/question/26334813
Answer:
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Explanation: