Answer:
a). 1.218 m/s
b). R=2.8
Explanation:


Momentum of the motion the first part of the motion have a momentum that is:


The final momentum is the motion before the action so:
a).




b).
kinetic energy

Kinetic energy after

Kinetic energy before

Ratio =

According to KE = (3/2)kT
reducing temperature, in KELVIN, by half, average KE is reduced by half.
Answer:
B = 8.0487mT
Explanation:
To solve the exercise it is necessary to take into account the considerations of the Magnetic Force described by Faraday,
The magnetic force is given by the formula

Where,
B = Magnetic Field
I = Current
L = Length
Angle between the magnetic field and the velocity, for this case are perpendicular, then is 90 degrees
According to our data we have that
I = 16.4A
F = 0.132N/m
As we know our equation must be modificated to Force per length unit, that is

Replacing the values we have that

Solving for B,


(1) friction is the force resisting the relative motion of solid surfaces , fluid layers and material elements sliding against each other.
(2) gravity is a science fiction .
(3) Resistance ::: is a property of a conductor by which the passage of current is opposed causing electric energy to be transformed into heat .
(4) viscosity is the quantity that describes a fluid.
(5)