Answer:
The ratio of the diameter of iron to Cu is;

Explanation:
R=(ρL)/A
- R is resistance,
- L is length,
- A is area,
- ρ is resistivity
- d is diameter
from the question the two materials have the same resistance per unit length.

for iron =
for copper
This means we can equate ρ/A for both materials.

re-arranging the equation we have,





A.
According to the equation: v=λ*f
λ stands for wavelength. wavelength increases, the frequency will decrease. lower frequency deserves low energy.
Answer:
Detailed step wise solution is attached below
Explanation:
(a) wavelength of the initial note 2.34 meters
(b) wavelength of the final note 0.389 meters
(d) pressure amplitude of the final note 0.09 Pa
(e) displacement amplitude of the initial note 4.78*10^(-7) meters
(f) displacement amplitude of the final note 3.95*10^(-8) meters
The increase in temperature of the metal hammer is 0.028 ⁰C.
The given parameters:
- <em>mass of the metal hammer, m = 1.0 kg</em>
- <em>speed of the hammer, v = 5.0 m/s</em>
- <em>specific heat capacity of iron, 450 J/kg⁰C</em>
The increase in temperature of the metal hammer is calculated as follows;

where;
<em>c is the </em><em>specific heat capacity</em><em> of the metal hammer</em>
<em />
Assuming the metal hammer is iron, c = 450 J/kg⁰C

Thus, the increase in temperature of the metal hammer is 0.028 ⁰C.
Learn more about heat capacity here: brainly.com/question/16559442