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 =

Electrons flow from the positive end of a source towards the negative end
Explain why the speed of light is lower than
3.0 × 108 m/s as it goes through different media.
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the molecules are forced to vibrate. that vib causes re emission. speed of emiited waves less than in vac.
Answer:
it must be helical motion in which the charge particle will move uniformly along z axis and simultaneously it will move in circular path in xy plane.
Explanation:
Magnetic field is along z axis while velocity is in x-z plane
so we will have

so here we can say

so we will have

so here the net force on the charge is perpendicular to its x directional velocity along - Y direction
So due to this component of motion it will move along a circle while other component of the motion will remain uniform always
So here it is combination of two parts
1) Uniform circular motion
2) Uniform motion
So we can say that it must be helical motion in which the charge particle will move uniformly along z axis and simultaneously it will move in circular path in xy plane.
answer:
yes
explanation:
At a separation of the surface of Earth (r=6400km) gravity wants pull the test mass closer and closer. ... So the work done by gravity is NEGATIVE. The gravitational potential energy is negative because us trying to do the opposite of what gravity wants needs positive energy.