Answer:
Potential Energy = x = m g h
Kinetic energy = 1/2 m v^2
Assuming the mass fall from rest
1/2 m v^2 = m g h
v^2 = 2 g h
So the speed attained is independent of the mass
Also, x / v does not have the units of mass
So the solution is none of the above.
Before answering this question, you must know the concept between extensive and intensive property. The extensive property does not depend on the amount of substance (like mass), which is the opposite of intensive properties. From the given choices, the rest are extensive properties except for <em>amount of matter</em>. Hence, that is the answer.
Answer:
1. 
2. 
Explanation:
Radial acceleration is:
(1)
With r the radius respects the axis of rotation and v the tangential velocity that is related with angular velocity (ω) by:
(2)
By (2) on (1):
To find the acceleration of the tube with the fall, we can use the expression:
(3)
Due impulse-momentum theorem:
(4)
with p the momentum and J the impulse. By (4) on (3):
And using Newton's second law (F=ma) and that (P=mv):
(5)
Final velocity is the velocity just after the encounter with hard floor, and initial momentum us just before that moment so the first one is zero and the second one can be found sing conservation of energy:
So (5) is:
solving for a:
It’s negative because is opposed to the tube movement.
Power is the rate work done given by dividing work done by unit time. It is measured in watts equivalent to J/s.
In this case the force by the student is mg = 490 N (taking g as 9.8m/s²)
Work done is given by force × distance,
Therefore, Power =(force × distance)/ time, but velocity/speed =distance/time
Thus, Power = force × speed/velocity
= 490 N × 1.25
= 612.5 J/S (Watts)
Hence, power will be 612.5 Watts.
