Answer:
a) R₁ = 14.1 Ω, b) R₂ = 19.9 Ω
Explanation:
For this exercise we must use ohm's law remembering that in a series circuit the equivalent resistance is the sum of the resistances
all resistors connected
V = i (R₁ + R₂)
with R₁ connected
V = (i + 0.5) R₁
with R₂ connected
V = (i + 0.25) R₂
We have a system of three equations with three unknowns for which we can solve it
We substitute the last two equations in the first
V = i ( )
1 = i ( )
1 = i ( ) =
i² + 0.75 i + 0.125 = 2i² + 0.75 i
i² - 0.125 = 0
i = √0.125
i = 0.35355 A
with the second equation we look for R1
R₁ =
R₁ = 12 /( 0.35355 +0.5)
R₁ = 14.1 Ω
with the third equation we look for R2
R₂ =
R₂ =
R₂ = 19.9 Ω
Answer:
Explanation:
Total energy is constant
E = mgh + ½mv² + Fd
At the top of the slide, all energy is potential
E = mgh + 0 + 0
At the bottom of the slide, all potential energy has converted to kinetic and work of friction.
mgh = ½mv² + W
W = mgh - ½mv²
W = 30.0[(9.81)(2.0) - ½6²]
W = 48.6 J