Answer:
Explanation:
Given
mass of rock
Elevation of Rock
Distance traveled by rock with time
where, u=initial velocity
t=time
a=acceleration
here initial velocity is zero
when rock is 5 m from ground then it has traveled a distance of 5 m from top because total height is 10 m
velocity at this time
Answer and Explanation:
This experiment is known as Lenz's tube.
The Lenz tube is an experiment that shows how you can brake a magnetic dipole that goes down a tube that conducts electric current. The magnet, when falling, along with its magnetic field, will generate variations in the magnetic field flux within the tube. These variations create an emf induced according to Faraday's Law:
This emf induced on the surface of the tube generates a current within it according to Ohm's Law:
This emf and current oppose the flux change, therefore a field will be produced in such a direction that the magnet is repelled from below and is attracted from above. The magnitude of the flux at the bottom of the magnet increases from the point of view of the tube, and at the top it decreases. Therefore, two "magnets" are generated under and above the dipole, which repel it below and attract above. Finally, the dipole feels a force in the opposite direction to the direction of fall, therefore it falls with less speed.
Answer:
a) KE = 888.26J
b) N = 294.5 turns
Explanation:
For the kinetic energy:
The inertia is:
So, the kinetic energy will be:
Now, friction force is:
Ff = μ*N = 0.80*5N = 4N
The energy balance would be:
Kf - Ko = Wf where Kf=0; Ko = 888.26J; and Wf is the work done by friction force.
Wf = -Ff*d = -Ff*N*2*π*R where N is the amount of turns it gives.
Replacing these values into the energy balance:
0-888.26=-4*N*2*π*0.12
-888.26=-0.96*π*N
N=294.5 turns