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
Science is an art, u cant make art without creativity
Answer:
The net displacement of the car is 3 km West
Explanation:
Please see the attached drawing to understand the car's trajectory: First in the East direction for 4 km (indicated by the green arrow that starts at the origin (zero), and stops at position 4 on the right (East).
Then from that position, it moves back towards the West going over its initial path, it goes through the origin and continues for 3 more km completing a moving to the West a total of 7 km. This is indicated in the drawing with an orange trace that end in position 3 to the left (West) of zero.
So, its NET displacement considered from the point of departure (origin at zero) to the final point where the trip ended, is 3 km to the west.
Answer:
22 km/h
Explanation:
Given that,
Speed of Xavier, v = 14 km/h
He tosses a set of keys forward on the ground at 8 km/h, v' = 8 km/h
We need to find the speed of the keys relative to the ground. Let it is V.
As both Xavier and the keys are moving in same diretion. The relative speed wrt ground is given by :
V = v+v'
V= 14 + 8
V = 22 km/h
So, the speed of the keys relative to the ground is 22 km/h.
Answer:
mechanical energy
Explanation:
In an electric motor the electrical energy is converted into mechanical energy. Almost every mechanical movement that we see around us is accomplished by an electric motor. Electric machines are a means of converting energy. Motors take electrical energy and produce mechanical energy.
