Answer:
F > W * sin(α)
Explanation:
The force needed for the box to start sliding up depends on the incline (α).
The external forces acting on the box would be the weight, the normal reaction and the lifting force that is applied to make it slide up.
These forces can be decomposed on their normal and tangential (to the slide plane) components.
The weight will be split into
Wn = W * cos(α) (in normal direction)
Wt = W * sin(α) (in tangential direction)
The normal reaction will be alligned with the normal axis, and will be equal to -Wn
N = -W* cos(α) (in normal direction)
To mke the box slide up, a force must be applied, that is opposite to the tangential component of the weight and at least a little larger
F > |-W * sin(α)| (in tangential direction)
Answer:
vf = 0
Explanation:
Since the initial height hi = 0, we can rewrite the energy equation as
vf^2 = vi^2 - 2ghf = (10 m/s)^2 - 2(10 m/s^2)(5 m) = 0
Therefore, his final velocity vf is
vf = 0
Explanation:
First we need to find the acceleration due to gravity on the planet. The wrench took 0.809 s to fall from a height of 4.50 m so we can use the equation
Solving for g, we get
Recall that the acceleration due to gravity on a planet's surface can be written as
We can express the mass of the planet 
in terms of its density 
as follows:
The expression for g then becomes
Solving for 
we get
![\:\:\:\:\:\:\:= \left[\dfrac{3(13.8\:\text{m/s}^2)}{4\pi (6.674×10^{-11}\:\text{Nm}^2\text{/kg}^2)(5500\:\text{kg/m}^3)}\right]](https://tex.z-dn.net/?f=%5C%3A%5C%3A%5C%3A%5C%3A%5C%3A%5C%3A%5C%3A%3D%20%5Cleft%5B%5Cdfrac%7B3%2813.8%5C%3A%5Ctext%7Bm%2Fs%7D%5E2%29%7D%7B4%5Cpi%20%286.674%C3%9710%5E%7B-11%7D%5C%3A%5Ctext%7BNm%7D%5E2%5Ctext%7B%2Fkg%7D%5E2%29%285500%5C%3A%5Ctext%7Bkg%2Fm%7D%5E3%29%7D%5Cright%5D)
Answer: You use it to cook food so you can eat. put whatever kind of food you like in there and heat it up for how long you want and then it will beep when done. then you can eat!
