Answer:
45° to min.
1° ----> 60 min
45° ----> ?.
45 * 60
2700 min
<h3><u>2</u><u>7</u><u>0</u><u>0</u><u> </u><u>min</u></h3>
<h3><u>Answer;</u></h3>
A.75°C
<h3><u>Explanation</u>;</h3>
Let the change in temp of cold water be x degrees,
while that of hot water be 100 - x degrees.
Heat exchange = mcΔt
Ice
Δt = x
m = 0.50 kg
c = 4.18 kJ/kg*°C
Hot water
Δt = 100 - x
m = 1.5 kg
c = 4.18
But;
Heat lost = heat gained
0.50 * c * x = 1.5 * c * (100 - x)
0.50 *x = 1.5*(100 - x)
0.5x = 150 - 1.5x
0.5x + 1.5x = 150 - 1.5x + 1.5x
2x = 150
x = <u>75° C</u>
Hence; the equilbrium temperature will be 75° C
For rectilinear motions, derived formulas all based on Newton's laws of motion are formulated. The equation for acceleration is
a = (v2-v1)/t, where v2 and v1 is the final and initial velocity of the rocket. We know that at the end of 1.41 s, the rocket comes to a stop. So, v2=0. Then, we can determine v1.
-52.7 = (0-v1)/1.41
v1 = 74.31 m/s
We can use v1 for the formula of the maximum height attained by an object thrown upwards:
Hmax = v1^2/2g = (74.31^2)/(2*9.81) = 281.42 m
The maximum height attained by the model rocket is 281.42 m.
For the amount of time for the whole flight of the model rocket, there are 3 sections to this: time at constant acceleration, time when it lost fuel and reached its maximum height and the time for the free fall.
Time at constant acceleration is given to be 1.41 s. Time when it lost fuel covers the difference of the maximum height and the distance travelled at constant acceleration.
2ax=v2^2-v1^2
2(-52.7)(x) = 0^2-74.31^2
x =52.4 m (distance it covered at constant acceleration)
Then. when it travels upwards only by a force of gravity,
d = v1(t) + 1/2*a*t^2
281.42-52.386 = (0)^2+1/2*(9.81)(t^2)
t = 6.83 s (time when it lost fuel and reached its maximum height)
Lastly, for free falling objects, the equation is
t = √2y/g = √2(281.42)/9.81 = 7.57 s
Therefore, the total time= 1.41+6.83+7.57 = 15.81 s
To compare and rank each one's acceleration, get the acceleration of each person by using the formula, Acceleration = Velocity/Time
Xander = 4.5mps / 3.5s = 1.29m/s^2
Finley = 3.6mps/4.2s = 0.86m/s^2
Max = 7.3mps/1.2s = 6.08m/s^2
Based on the answers above, the least acceleration was done by Finley, then Xander had higher acceleration than Finley, while most acceleration was done by Max.
