Answer:
Upward
Explanation:
We are given that
Mass of scarp paper,
1mg=
Distance,d =8 mm=
Magnitude of electric force =
Where 
Substitute the values
Gravitational force act in downward direction.
The electric force acts in opposite direction and magnitude of electric force is equal to gravitational force.
Hence, the direction of electric force is upward.
Because they are mentally trying to extinguish the negative things in their lives and focus on the positive things
Answer:
b) N = 560 N, c) fr = 138.56 N, d) μ = 0.247
Explanation:
a) In the attachment we can see the free body diagram of the system
b) Let's write Newton's second law on the y-axis
N + T_y -W = 0
N = W -T_y
let's use trigonometry for tension
sin θ = T_y / T
cos θ = Tₓ / T
T_y = T sin θ
Tₓ = T cos θ
we substitute
N = W - T sin 30
we calculate
N = 640 - 160 sin 30
N = 560 N
c) as the system goes at constant speed the acceleration is zero
X axis
Tₓ - fr = 0
Tₓ = fr
we substitute and calculate
fr = 160 cos 30
fr = 138.56 N
d) the friction force has the formula
fr = μ N
μ = fr / N
we calculate
μ = 138.56 / 560
μ = 0.247
This question is checking to see whether you understand the meaning
of "displacement".
Displacement is a vector:
-- Its magnitude (size) is the distance between the start-point and
the end-point, no matter what route might have been followed along
the way.
-- Its direction is the direction from the start-point to the end-point.
Talking about the Earth's orbit around the sun, we can forget about
the direction of the displacement, and just talk about its magnitude
(size).
If we pretend that the sun is not moving and dragging the whole
solar system along with it, then what do we see the Earth doing
in one year ?
We mark the place where the Earth is at the stroke of midnight
on New Year's Eve. Then we watch it as it swings around through
this gigantic orbit, all the way around the sun, and in a year, it's back
to the same point that we marked !
So what's the magnitude of the displacement in exactly one year ?
It's the distance between the start-point and the end-point. But the
Earth came back to the same place it started from, so there's no
separation at all between the start-point and the end-point.
The Earth covered a huge distance in that year, but the displacement
is zero.
