Answer:
c
Explanation:
Friction is caused by how rough and object is, and how much the object weighs, as this causes it to drag more.
(a) No, because the mechanical energy is not conserved
Explanation:
The work-energy theorem states that the work done by the engine on the airplane is equal to the gain in kinetic energy of the plane:
(1)
However, this theorem is only valid if there are no non-conservative forces acting on the plane. However, in this case there is air resistance acting on the plane: this means that the work-energy theorem is no longer valid, because the mechanical energy is not conserved.
Therefore, eq. (1) can be rewritten as
which means that the work done by the engine (W) is used partially to increase the kinetic energy of the airplane (
) and part is lost because of the air resistance (
).
(b) 77.8 m/s
First of all, we need to calculate the net force acting on the plane, which is equal to the difference between the thrust force and the air resistance:
Now we can calculate the acceleration of the plane, by using Newton's second law:
where m is the mass of the plane.
Finally, we can calculate the final speed of the plane by using the equation:
where
is the final velocity
is the initial velocity
is the acceleration
is the distance travelled
Solving for v, we find
if a volume of air is warmed it expands due to increased translational kinetic energy as it expands it will start to cool.
<h3>When does temperature increase volume?</h3>
We can then conclude that at constant pressure, temperature and volume are directly proportional: temperature increases, volume increases; decrease temperature, decrease volume.
In this case, the higher the temperature, the greater the kinetic energy that acts on the molecules of this gas, so when the gas expands, these molecules find more space and collide less, which will cause the gas to cool.
See more about volume at brainly.com/question/1578538
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Answer:
Mass, m = 6.18 kg
Explanation:
Given the following data;
Frequency, F = 10 Hz
Spring constant, k = 250 N/m
We know that pie, π = 22/7
To find the mass, we would use the following formula;
F = 1/2π√(k/m)
Where;
F is the frequency of oscillation.
k is the spring constant.
m is the mass of the spring.
Substituting into the formula, we have;
10 = 1/2 * 22/7 * √250/m
10 = 22/14 * √250/m
Cross-multiplying, we have;
140 = 22 * √250/m
Dividing both sides by 22, we have;
140/22 = √250/m
6.36 = √250/m
Taking the square of both sides, we have;
6.36² = (√250/m)²
40.45 = 250/m
Cross-multiplying, we have;
40.45m = 250
Mass, m = 250/40.45
Mass, m = 6.18 kg
Answer:
1.5 hours
Explanation:
Using the equation t=d/v to solve for time:
t=75 miles ÷ 50 miles per hour = 1.5 hours
