Answer:
The box will travel 1.2 [m]
Explanation:
This problem can easily be solved by using the principle of work and energy conservation which expresses that, when the particle moves from A1 to A2 under the action of an F force, the work of the F Force is equal to the change of the kinetic energy of the particle. The above is known as the principle of work and energy.
In the attached image we can see the conditions of this particular case, and we will analize each member of the equations deducted:
Kinetic energy (position 1):
![E_{k1}=\frac{1}{2}*m*v_{0}^{2} \\E_{k1}=\frac{1}{2} *2.5*(3.9)^{2} \\E_{k1}=19 [J]](https://tex.z-dn.net/?f=E_%7Bk1%7D%3D%5Cfrac%7B1%7D%7B2%7D%2Am%2Av_%7B0%7D%5E%7B2%7D%20%5C%5CE_%7Bk1%7D%3D%5Cfrac%7B1%7D%7B2%7D%20%2A2.5%2A%283.9%29%5E%7B2%7D%20%5C%5CE_%7Bk1%7D%3D19%20%5BJ%5D)
Position 2 (work):
![W= - f_{fri}*x - (m*g*sin(23))*x\\W= - f_{fri}*x - (2.5*9.81*sin(23))*x\\\\W= - (f_{fri}* +9.5)*x\\](https://tex.z-dn.net/?f=W%3D%20-%20f_%7Bfri%7D%2Ax%20-%20%28m%2Ag%2Asin%2823%29%29%2Ax%5C%5CW%3D%20-%20f_%7Bfri%7D%2Ax%20-%20%282.5%2A9.81%2Asin%2823%29%29%2Ax%5C%5C%5C%5CW%3D%20-%20%28f_%7Bfri%7D%2A%20%2B9.5%29%2Ax%5C%5C)
Principle of work and energy:
![Ek_{1} +W=Ek_{2} \\Ek_{1} +W=0 \\\\Ek_{1} =-W \\](https://tex.z-dn.net/?f=Ek_%7B1%7D%20%2BW%3DEk_%7B2%7D%20%5C%5CEk_%7B1%7D%20%2BW%3D0%20%5C%5C%5C%5CEk_%7B1%7D%20%3D-W%20%5C%5C)
![19=(f_{fri} +9.5 )*x](https://tex.z-dn.net/?f=19%3D%28f_%7Bfri%7D%20%2B9.5%20%29%2Ax)
In the last equation we need to clear x, but first we need to find the value for the friction force, Therefore in the attached image we can find the study of forces in the y axis where we cand find the normal force, then knowing the friction factor we will determine the friction force.
![x=\frac{19}{(f_{fri}+9.5 )} \\x=\frac{19}{(6.09+9.5 )} \\\\x=1.21[m]](https://tex.z-dn.net/?f=x%3D%5Cfrac%7B19%7D%7B%28f_%7Bfri%7D%2B9.5%20%29%7D%20%5C%5Cx%3D%5Cfrac%7B19%7D%7B%286.09%2B9.5%20%29%7D%20%5C%5C%5C%5Cx%3D1.21%5Bm%5D)
Answer:
The speed of the cart decreases
Explanation:
The track is frictionless, so we can consider the cart as isolated system (no external forces acting on it): therefore, the momentum of the cart is conserved
![p=mv=const.](https://tex.z-dn.net/?f=p%3Dmv%3Dconst.)
where m is the mass and v the speed of the cart.
When it starts raining, some water falls into the cart: this means that the mass of the cart, m, increases. But we said that the momentum, p, must remain constant: in order for that to happen, this means that the speed of the cart, v, must decrease (because the relationship
is an inverse relationship, so if m increases, v must decrease).
![Electric~potential ~energy~U_{E}=K_{e}.\dfrac{Qq}{R}\\so~ U_{E} \propto \dfrac{1}{R}](https://tex.z-dn.net/?f=Electric~potential%20~energy~U_%7BE%7D%3DK_%7Be%7D.%5Cdfrac%7BQq%7D%7BR%7D%5C%5Cso~%20U_%7BE%7D%20%5Cpropto%20%5Cdfrac%7B1%7D%7BR%7D%20)
so to increase Ue by 16 times you gotta reduce R(distence) by 16 times
Microwaves are most energy efficient way to send information.
<h3>What are SETI programs?</h3>
Electromagnetic waves are a general term for familiar light and radio waves, but they also include gamma rays, X-rays, ultraviolet rays, and infrared rays. All of these forms of electromagnetic radiation or waves travel at the speed of light, the highest possible speed. The only difference between these types of electromagnetic waves is their length, or wave, or "wavelength." Another way to characterize waves is the number of waves received per second, since they all travel at the speed of light. This is the wave frequency. A specific range of radio frequencies from 1 GHz to 10 GHz, "microwaves", is particularly well suited for interstellar communications. At lower frequencies, our galaxy emits enormous amounts of radio waves, creating a large amount of background noise. At higher frequencies, the Earth's atmosphere, and possibly other Earth-like planets, absorb and emit a wide range of radio frequencies. The result is a quiet "microwave window" that enables efficient wireless communication.
To know more about SETI programs visit:
brainly.com/question/29432753
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