Answer:
I = 4 A
Explanation:
When the batteries are connected in parallel, the voltage is the same as the voltage of each battery, but the internal resistance is less, in general we can assume that the internal resistance is also in parallel.
1 / 
= 1 / r₁ + 1 / r₂ = 2 / r = 2/1
r_{eq} = 0.5 ohm
The current in the resistor is
V = I R + I r_{eq}
I = V / R + r_{eq}
I = 18 / (4 +0.5)
I = 4 A
Answer: a) v = ω /k, b) v = - ωAcos( kx −ωt)
Explanation:
y(x,t)=Asin(kx−ωt) defines the wave equation.
a)
We are asked to find wave speed (v)
Recall that v = fλ
From the wave equation above,
k = 2π/ λ where k is the wave number and λ is the wavelength, λ = 2π /k
ω = 2πf where f is the frequency and ω is the angular frequency.
f = ω/ 2π.
By substituting for λ and ω into the wave speed formulae, we have that
v =( ω/ 2π) × (2π /k)
v = ω/k
b)
y(x,t)=Asin(kx−ωt)
The first derivative of y with respect to x give the velocity (vy)
By using chain rule, we have that
v = dy/dt = A cos( kx −ωt) × (−ω)
v = - ωAcos( kx −ωt)
Answer:
The river bank can expand due to the water breaking apart which can cause sediment to move and change/erode
Answer a is one of keplers 3 laws
