C. zinc is best used for making screws. Zinc is best used for making alloys, anything made from 55% or 95% copper more then likely contain zinc
Answer:
Your answer would be D. be pushed down into their seats.
Explanation:
You can think of it this way:
If you're not wearing a seat belt on an airplane that drops suddenly, in this case, vertically, which often happens with turbulence- you're the one at rest. You'll stay at rest as the plane (literally) drops out from under you.
If you're strapped in, the seat belt serves as an outside force acting on you, taking you with the plane as it drops and saving you from hitting the ceiling.
Always remember Newton's first law of motion: A body at rest will remain at rest unless an outside force acts on it.
A pulley is another sort of basic machine in the lever family. We may have utilized a pulley to lift things, for example, a banner on a flagpole.
<u>Explanation:</u>
The point in a fixed pulley resembles the support of a lever. The remainder of the pulley behaves like the fixed arm of a first-class lever, since it rotates around a point. The distance from the fulcrum is the equivalent on the two sides of a fixed pulley. A fixed pulley has a mechanical advantage of one. Hence, a fixed pulley doesn't increase the force.
It essentially alters the direction of the force. A moveable pulley or a mix of pulleys can deliver a mechanical advantage of more than one. Moveable pulleys are appended to the item being moved. Fixed and moveable pulleys can be consolidated into a solitary unit to create a greater mechanical advantage.
Answer:
Explanation:
To find the angular velocity of the tank at which the bottom of the tank is exposed
From the information given:
At rest, the initial volume of the tank is:
where;
height h which is the height for the free surface in a rotating tank is expressed as:
at the bottom surface of the tank;
r = 0, h = 0
∴
0 = 0 + C
C = 0
Thus; the free surface height in a rotating tank is:
Now; the volume of the water when the tank is rotating is:
dV = 2π × r × h × dr
Taking the integral on both sides;
replacing the value of h in equation (2); we have:
![V_f = \dfrac{ \pi \omega ^2}{g} \Big [ \dfrac{r^4}{4} \Big]^R_0](https://tex.z-dn.net/?f=V_f%20%3D%20%5Cdfrac%7B%20%5Cpi%20%5Comega%20%5E2%7D%7Bg%7D%20%5CBig%20%5B%20%20%5Cdfrac%7Br%5E4%7D%7B4%7D%20%5CBig%5D%5ER_0)
![V_f = \dfrac{ \pi \omega ^2}{g} \Big [ \dfrac{R^4}{4} \Big] --- (3)](https://tex.z-dn.net/?f=V_f%20%3D%20%5Cdfrac%7B%20%5Cpi%20%5Comega%20%5E2%7D%7Bg%7D%20%5CBig%20%5B%20%20%5Cdfrac%7BR%5E4%7D%7B4%7D%20%5CBig%5D%20---%20%283%29)
Since the volume of the water when it is at rest and when the angular speed rotates at an angular speed is equal.
Then 
Replacing equation (1) and (3)
Finally, the angular velocity of the tank at which the bottom of the tank is exposed = 10.48 rad/s
The neutron is uncharged. That's why it was
given a name built on "neu" from "neutral".
