Answer:
2560J
Explanation:
By definition the kinetic energy can be calculated in the following way:
K = (mv²)/2 = 80kg·(8.0m/s)²/2 = 2560 J
Answer:
Frequency and wavelength are inversely proportional to each other. The wave with the greatest frequency has the shortest wavelength. Twice the frequency means one-half the wavelength. For this reason, the wavelength ratio is the inverse of the frequency ratio.
<span>This problem is relatively simple, in order to solve this problem the only formula you need to know is the formula for friction, which is:
Ff = UsN
where Us is the coefficient of static friction and N is the normal force.
In order to get the crate moving you must first apply enough force to overcome the static friction:
Fapplied = Ff
Since Fapplied = 43 Newtons:
Fapplied = Ff = 43 = UsN
and it was given that Us = 0.11, so all you have to do is isolate N by dividing both sides by 0.11
43/0.11 = N = 390.9 which is approximately 391 or C. 3.9x10^2</span>
Answer:
The answer is below
Explanation:
The length of the rope is equal to the radius of the circle formed by the complete rotation of the rope. Therefore the radius = 1.50 m.
a) The distance covered by the rope when completing one rotation is the same as the perimeter of the circle. Hence:
Distance covered in one rotation = 2π * radius = 2π * 1.5 = 3π meters
The velocity of the ball = Distance / time = 3π meters / 3.4 seconds = 2.77 m/s
b) The initial velocity (u) is 0 m/s, the final velocity is 2.77 m/s during time (t) = 3.4 s. Hence acceleration (a):
v = u + at
2.77 = 3.4a
a = 0.82 m/s²
c) Force on ball = mass * acceleration = 4 * 0.82 = 3.28 N
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.
