Answer:
options A and C
Explanation:
Since, the spheres are of same size and rotational speed of the sphere are not dependent on their masses. So, both the sphere will reach the bottom of the at the same time with the same speed. But their kinetic energies are different.
So, options A and C are correct.
Answer:
It is<em> impossible</em> to construct a machine which produces the <em>work output greater than the work input.</em>
Let us consider the II law of thermodynamics.
According to Kelvin Plank's statement any engine/machine does not give hundred percent efficiency. And violating the PMM-II(Perpetual motion of machine II kind), Always some amount of energy transferred to the sink or surroundings.
Therefore
W(ouput) = Q₁-Q₂
There are many reasons to lower the work output, just for an example friction between the mating parts reduces the work output.
Answer:
w=3.05 rad/s or 29.88rpm
Explanation:
k = coefficient of friction = 0.3900
R = radius of the cylinder = 2.7m
V = linear speed of rotation of the cylinder
w = angular speed = V/R or to rewrite V = w*R
N = normal force to cylinder
N=


These must be balanced (the net force on the people will be 0) so set them equal to each other.





There are 2*pi radians in 1 revolution so:

So you need about 30 RPM to keep people from falling out the bottom
He produced the first orderly arrangement of known elements, he used patterns to predict undiscovered elements
Answer:
Impulse = 322.5[kg*m/s], the answer is D
Explanation:
This method it is based on the principle of momentum and the amount of movement; and used to solve problems involving strength, mass, speed and time.
If units of the SI are used, the magnitude of the impulse of a force is expressed in N * s. however, when remembering the definition of the newton.

Now replacing the values on the following equation that express the definition of impulse
![Impulse = Force * Time\\\\Impulse = 215 * 1.5 = 322.5 [kg*m/s]](https://tex.z-dn.net/?f=Impulse%20%3D%20Force%20%2A%20Time%5C%5C%5C%5CImpulse%20%3D%20215%20%2A%201.5%20%3D%20322.5%20%5Bkg%2Am%2Fs%5D)