Answer:
T_finalmix = 59.5 [°C].
Explanation:
In order to solve this problem, a thermal balance must be performed, where the heat is transferred from water to methanol, at the end the temperature of the water and methanol must be equal once the thermal balance is achieved.
where:
mwater = mass of the water = 0.4 [kg]
Cp_water = specific heat of the water = 4180 [J/kg*°C]
T_waterinitial = initial temperature of the water = 85 [°C]
T_finalmix = final temperature of the mix [°C]
Now replacing:
![0.4*4180*(85-T_{final})=0.4*2450*(T_{final}-16)\\142120-1672*T_{final}=980*T_{final}-15680\\157800=2652*T_{final}\\T_{final}=59.5[C]](https://tex.z-dn.net/?f=0.4%2A4180%2A%2885-T_%7Bfinal%7D%29%3D0.4%2A2450%2A%28T_%7Bfinal%7D-16%29%5C%5C142120-1672%2AT_%7Bfinal%7D%3D980%2AT_%7Bfinal%7D-15680%5C%5C157800%3D2652%2AT_%7Bfinal%7D%5C%5CT_%7Bfinal%7D%3D59.5%5BC%5D)
If you only know its speed, that's not enough information to catch it. You could even chase it at DOUBLE that speed, and you'd never catch it if you were chasing in the wrong direction.
You also have to know the DIRECTION the runaway car is going, so that you can chase in the same direction.
Now that you know its speed AND direction, you know its velocity. You need that information to have any chance of catching it.
A. Impulse is simply the product of Force and time.
Therefore,
I = F * t --->
1
where I is impulse, F is force, t is time
However another formula for solving impulse is:
I = m vf – m vi --->
2
where m is mass, vf is final velocity and vi is initial
velocity
Therefore using equation 2 to solve for impulse I:
I = 2000kg (0) – 2000kg (77 m/s)
I = -154,000 kg m/s
B. By conservation of momentum, we also know that Impulse
is conserved. That means that increasing the time by a factor of 3 would still
result in an impuse of -154,000 kg m/s. So,
I = F’ * (3 t) = -154,000 kg m/s
Since t is multiplied by 3, therefore this only means
that Force is decreased by a factor of 3 to keep the impulse constant,
therefore:
(F/3) (3t) = -154,000 kg m/s
Summary of Answers:
A. I = -154,000 kg m/s
B. Force is decreased by factor of 3
Answer: gamma rays < ultraviolet light < radio waves
Explanation: We have to explain the ordering we take into account a relationship for electromagnetic wave, which is given by:
c=λ*ν c is the speed of light. λ and ν are the wavelegth and the frequency of the waves.
Then we also know that the high frequency of these radiation correspond to the gamma ray (10^18 1/s) while the lowest correspond to radio wave (10^8 1/s) so:
The ultraviolet ligth is ranged at frequencies of 10^16 1/s located bewteen gamma and radio radiation.
as large frequency lower wavelength we can order these radiations from short to long wavelengths as follows:
gamma rays < ultraviolet light < radio waves
