Answer:
Velocity = 20.3 [m/s]
Explanation:
This is a typical problem of energy conservation, where potential energy is converted to kinetic energy. We must first find the potential energy. In this way, we will choose as a reference point or point where the potential energy is zero when the carrriage rolls down 21 [m] from the top of the hill.
![E_{p} =m*g*h\\ where:\\m = mass = 25[kg]\\g = gravity = 9.81 [m/s^2]\\h = elevation = 21 [m]\\E_{p} =potential energy [J]\\E_{p} =25*9.81*21=5150[J]](https://tex.z-dn.net/?f=E_%7Bp%7D%20%3Dm%2Ag%2Ah%5C%5C%20where%3A%5C%5Cm%20%3D%20mass%20%3D%2025%5Bkg%5D%5C%5Cg%20%3D%20gravity%20%3D%209.81%20%5Bm%2Fs%5E2%5D%5C%5Ch%20%3D%20elevation%20%3D%2021%20%5Bm%5D%5C%5CE_%7Bp%7D%20%3Dpotential%20energy%20%5BJ%5D%5C%5CE_%7Bp%7D%20%3D25%2A9.81%2A21%3D5150%5BJ%5D)
Now this will be the same energy transformed into kinetic energy, therefore:
![E_{p}=E_{k} = 5150[J]\\E_{k} =0.5*m*v^{2} \\where:\\v=velocity [m/s]\\v=\sqrt{\frac{E_{k}}{0.5*25} } \\v=20.3[m/s]](https://tex.z-dn.net/?f=E_%7Bp%7D%3DE_%7Bk%7D%20%3D%205150%5BJ%5D%5C%5CE_%7Bk%7D%20%3D0.5%2Am%2Av%5E%7B2%7D%20%5C%5Cwhere%3A%5C%5Cv%3Dvelocity%20%5Bm%2Fs%5D%5C%5Cv%3D%5Csqrt%7B%5Cfrac%7BE_%7Bk%7D%7D%7B0.5%2A25%7D%20%7D%20%5C%5Cv%3D20.3%5Bm%2Fs%5D)
Answer:
The human retina can only detect incident light that falls in waves 400 to 720 nanometers long, so we can't see microwave or ultraviolet wavelengths. This also applies to infrared lights which has wavelengths longer than visible and shorter than microwaves, thus being invisible to the human eye.
Answer:
Explanation:
1- incident ray
2- the substance through which the wave travels
Answer:
Looks like <em>Trigonal Planar</em>
Explanation:
There are only 3 areas of electron density and no unpaired electrons on the central atom, which indicates trigonal planar. This image might help...
