Cold air cannot escape a freezer due to there being no conductors for it to transfer heat with in other words no other energy to transfer with
<span>the scientific study of the human mind and its functions..</span>
Answer:
The velocity will be v = 165.83[m/s]
Explanation:
This is a problem where the definition of kinetic energy can be applied, which can be determined with the following equation.
![E_{k}=\frac{1}{2}*m*v^{2}\\ where:\\m = mass = 80000[kg]\\v = velocity [m/s]\\E_{k}= kinetic energy [J]=1100000000[J]\\Replacing:\\v=\sqrt{\frac{2*E_{k} }{m} } \\v=\sqrt{\frac{2*1100000000 }{80000} }\\v=165.83[m/s]](https://tex.z-dn.net/?f=E_%7Bk%7D%3D%5Cfrac%7B1%7D%7B2%7D%2Am%2Av%5E%7B2%7D%5C%5C%20%20%20where%3A%5C%5Cm%20%3D%20mass%20%3D%2080000%5Bkg%5D%5C%5Cv%20%3D%20velocity%20%5Bm%2Fs%5D%5C%5CE_%7Bk%7D%3D%20kinetic%20energy%20%5BJ%5D%3D1100000000%5BJ%5D%5C%5CReplacing%3A%5C%5Cv%3D%5Csqrt%7B%5Cfrac%7B2%2AE_%7Bk%7D%20%7D%7Bm%7D%20%7D%20%5C%5Cv%3D%5Csqrt%7B%5Cfrac%7B2%2A1100000000%20%7D%7B80000%7D%20%7D%5C%5Cv%3D165.83%5Bm%2Fs%5D)
Answer:
0.5sec
Explanation:
Parameters
Height(H) =20m
Initial velocity(u) = 5m/s
Acceleration due to gravity(g) =10m/s^2
Method one
Using the second law of motion
H=ut-1/2gt^2
20=5t-1/2×10×t^2
20=5t-5t^2
dh/dt = 5-10t
where any constant is zero therefore the 20 is zero
5-10t=0
Collect like terms
-10t= -5
t=1/2 = 0.5sec
2nd method
Parameters
Height(H) =20m
Initial velocity(u) = 5m/s
Acceleration due to gravity(g) =10m/s^2
Using the time taken formula
t=u/g
t=5/10
t=0.5sec
Answer:
Explanation:
Because the total energy available to the ball doesn't change whatsoever during its entire trip from the window to the ground,
TE = KE + PE which says that the total energy available to a system is equal to the kinetic energy of the system plus the potential energy, and that this value will not ever change (because energy cannot be created or destroyed. Sound familiar?) If the ball is being held still before it is dropped from some height off the ground, it is here that the total energy can be determined, and that total energy at this point is all potential, since the ball is not moving while someone is holding it and getting ready to drop it. The SECOND it starts to fall, the potential energy begins to be converted to kinetic. As the potential energy is losing value, the kinetic is gaining it at the same rate (again, energy doesn't just disappear; it has to go somewhere. Here, it goes from potential to kinetic a little at a time). When the ball finally hits the ground, or an INSTANT BEFORE it hits the ground, the potential energy is 0 because the height of something on the ground has a height of 0. At this instant, right before the ball hits the ground, is where the KE is the greatest. All the energy at that point has been converted from potential to kinetic.
Long story short, choice B is the one you want.
