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) T = 2.26 N, b) v = 1.68 m / s
Explanation:
We use Newton's second law
Let's set a reference system where the x-axis is radial and the y-axis is vertical, let's decompose the tension of the string
sin 30 =
cos 30 =
Tₓ = T sin 30
T_y = T cos 30
Y axis
T_y -W = 0
T cos 30 = mg (1)
X axis
Tₓ = m a
they relate it is centripetal
a = v² / r
we substitute
T sin 30 = m (2)
a) we substitute in 1
T =
T =
T = 2.26 N
b) from equation 2
v² =
If we know the length of the string
sin 30 = r / L
r = L sin 30
we substitute
v² =
v² =
For the problem let us take L = 1 m
let's calculate
v =
v = 1.68 m / s