Answer:
a) R = ρ₀ L /π(r_b² - R_a²)
, b) ρ₀ = V / I π (r_b² - R_a²) / L
Explanation:
a) The resistance of a material is given by
R = ρ l / A
where ρ is the resistivity, l is the length and A is the area
the length is l = L and the resistivity is ρ = ρ₀
the area is the area of the cylindrical shell
A = π r_b² - π r_a²
A = π (r_b² - r_a²)
we substitute
R = ρ₀ L /π(r_b² - R_a²)
b) The potential difference is related to current and resistance by ohm's law
V = i R
we subsist the expression of resistance
V = I ρ₀ L /π (r_b² - R_a²)
ρ₀ = V / I π (r_b² - R_a²) / L
Answer:
Hearing loss due to sound energy damaging the nerve cells in the inner ear. Many animals behavior is influenced by sound energy. They learn to associate events with sounds, so they run when something crunches in the dry grass (might be a coyote), but won't be bothered by the sound of a waterfall. Mood is affected by sound energy. A wine glass can break with sound energy, if the frequency matches the resonant frequency of the wine glass and the amplitude is great enough (one Mythbusters show featured a professional singer who broke a wine glass with his voice without any amplification).
Sound energy causes the particles in the medium it is traveling through to vibrate.
Unlike sound electromagnetic waves can travel trough empty space
hope these different answers help
Explanation:
A simple way to state Newton's first law is:
For every action force, there is a reaction force which is equal in magnitude and opposite in direction.
Answer:
C) If an ice cube is placed into a boiling water, then it will melt in less than 2 minutes.
Explanation:
The volume of the block of wood is given by length × width ×height
= 2.75 × 4.80 × 7.5
= 99 cm³
Density is given by mass/volume
Thus = 84.0 g/ 99 cm³
= 0.848 g/cm³
Hence; since the block is less dense than water (1 g/cm³) it will float
