Answer:
0 N/C
Explanation:
Parameters given:
The distance between 
and 
is
Electric field is given as
r = 15/2 = 7.5cm = 0.075m
The electric field at their midpoint due to is:
= 
The electric field at the midpoint due to is:
= 
The net electric field will be:
E = +
E = 
+ 
E = 0 N/C
Consider the formula ...
Current = (voltage) / (resistance) .
If the resistance doesn't change, then the current is
directly proportional to the voltage.
If the voltage decreases to 1/3 of what it used to be,
then the current does the same thing.
1.2 A ----> 0.4 A
Answer:
y = 12.82 m
Explanation:
We can solve this exercise using the energy work theorem
W = ΔEm
friction force work is
W = fr . s = fr s cos θ
the friction force opposes the movement, therefore the angle is 180º
W = - fr s
we write Newton's second law, where we use a reference frame with one axis parallel to the plane and the other perpendicular
N -Wy = 0
N = mg cos θ
the friction force remains
fr = μ N
fr = μ mg cos θ
work gives
W = - μ mg s cos θ
initial energy
Em₀ = ½ m v²
the final energy is zero, because it stops
we substitute
- μ m g s cos θ = 0 - ½ m v²
s = ½ v² / (μ g cos θ)
let's calculate
s = ½ 20² / (0.55 9.8 cos 20)
s = 39.49 m
this is the distance it travels along the plane, to find the vertical distance let's use trigonometry
sin 20 = y / s
y = s sin 20
y = 37.49 sin 20
y = 12.82 m
