Answer:
9.34 N
Explanation:
First of all, we can calculate the speed of the wave in the string. This is given by the wave equation:
where
f is the frequency of the wave
is the wavelength
For the waves in this string we have:
, since it completes 625 cycles per second
is the wavelength
So the speed of the wave is
The speed of the waves in a string is related to the tension in the string by
(1)
where
T is the tension in the string
is the linear density
In this problem:
is the mass of the string
L = 0.75 m is the its length
Solving the equation (1) for T, we find the tension:
I can't see that cube from here.
But if the length of the side of the cube is ' K ' units,
then the surface area of the cube is 6K² units², and
the volume of the cube is K³ units³.
The ratio of the surface area to the volume is
(6K² units²) / (K³ units³) = (6) / (K units) .
So for example, if the side of the cube is 2 inches, then
the ratio of surface area to volume is "3 per inch".
That's the answer. I did the whole thing in order to earn
the points, but I don't expect you to understand much of it,
because I see from your username that you suck at math.
I'm sorry you decided that. Now that you've put up the
brick wall, it'll be even harder for any math to find its way
in there, and you'll miss out on a lot of the fun.
A comet is the loose, icy body with a long, narrow orbit.
Comets are very small solar system body made mainly of ices mixed with smaller amounts of dust and rock. Most comets are not larger than a few kilometers across. The main body of the comet is called the nucleus, and it can contain water, methane, nitrogen and other ices. Their speeds vary depending on their orbits and where they are in it. The closer they are to the sun, the faster they are going.
The correct answer is
<span>c. one person exerts more force than the other so that the forces are unbalanced.
In fact, the door is initially at rest. In order to move the door, a net force different from zero should be applied, according to Newton's second law:
</span>
<span>where the term on the left is the resultant of the forces acting on the door, m is the door mass and a its acceleration.
In order to move the door, the acceleration must be different from zero. But this means that the resultant of the forces acting on it must be different from zero: this is possible only if the forces applied by the two persons are unbalanced, i.e. one person exerts more force than the other.</span>