Answer:
Explanation:
For calculating resistance of a conductor , the formula is
R = ρ l / A , ρ is specific resistance , l is length and A is cross sectional area of wire.
For first wire length is l₁ , area is A₁ resistance is R₁, for second resistance is R₂ , length is l₂ and area is A₂
Given , l₁ = 2l₂ , A₁ = 4A₂ , area is proportional to square of thickness.
R₁ / R₂ = I₁A₂ / I₂A₁
= 2l₂ x A₁ / 4 I₂A₁
= 1 / 2
2R₁ = R₂
Power = V² / R
Ratio of power = (V² / R₁) x (R₂ / V²)
= R₂ / R₁
= 2 .
Answer:
α= 1.3 10-5 ºC⁻¹
Explanation:
La dilatación termica de los cuerpos esta dada por la relación
ΔL = L₀ α ( T -T₀)
en este caso nos piden el coeficiente de dilatación térmica
α =DL/L₀ DT
calculemos
α = ( 100,13 -100)/[100 (100 – 0)]
α = 1,3 10-5 ºC⁻¹
Traduction
The thermal expansion of bodies is given by the relationship
ΔL = L₀ α (T -T₀)
in this case they ask us for the coefficient of thermal expansion
α = ΔL / L₀ ΔT
let's calculate
α = (100,13 -100) / [100 (100 - 0)]
α= 1.3 10-5 ºC⁻¹
Mass, m=22 kg
It is given that Force, F = 88N
Acceleration, a=4 m/s 2
Answer: It is both B and D
Select all that apply.
At night, thermal energy moves _____.
from space to the atmosphere
from the land to the atmosphere
from the atmosphere to the land
from the atmosphere to space
a. There is nothing suggesting that the balloon is accelerating horizontally, so we can assume that its horizontal speed is constant. The time before the balloon crash into the hill is simply the distance between the balloon and the hill divided by its velocity. Remember that velocity is simply the amount of distance that a object travels in a certain amount of time:

b. Know that you know the maximum amount of time that the balloon can take to gain 28m of altitude, the minimum acceleration can be found using the equations constant acceleration motion:

where a is the acceleration, v_o is the initial vertical velocity, 0 as the balloon is not moving vertically before starting to ascend. xo is the initial position, which we will give a value of 0m.

c. As we said before, there isn't any kind of force that accelerates the balloon horizontally, therefore, we can consider that its horizontal velocity is constant and equal to 2.8m/s
d. Acceleration is the amount of change in velocity after a given amount of time. So, with the acceleration and the time we can fin the velocity:
