Answer:
80Ω
Explanation:
Resistance in a series circuit (when one resistor is after another in the same line) is calculated with the following equation
Total resistance = R1 + R2 + R3...Rn
Substitute in your values and solve for total resistance
Total resistance = 60 + 20 = 80Ω
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:
For cast iron we have

For copper

For Lead

For Zinc

Explanation:
As we know that final speed of the block is calculated by work energy theorem

now we have

now we have


For cast iron we have


For copper


For Lead


For Zinc


When the diver reaches maximum height, the upward velocity will be zero.
We shall use the formula
v^2 = u^2 - 2gh
where
v = 0 (velocity at maximum height)
u = 1.2 m/s, intial upward velocity
g = -9.8 m/s^2, gravitational acceleration (downward)
h = maximum height attained above the diving board.
Therefore
0 = 1.2^2 - 2*9.8*h
h = 1.2^2/(2*9.8) = 0.0735 m
Answer: 0.074 m (nearest thousandth)
I think it's D because sunlight is a solar system