Answer:
Starting from the beginning.
There is a radio signal that is received by the radio.
The radio interprets the signal and produces a current in response to it.
That current goes to a membrane that oscillates producing sound, the oscillation of the membrane is the first mechanical energy event here.
These oscillations can travel in material mediums, for example, the air. Then there is a production of waves (soundwaves) that travel in the air (second event).
Those waves now hit the wall that separates you and your neighbor, as the wall is made of a material, the soundwaves can travel through it, but they will be dispersed (a part of the waves rebounds on the wall, and another part is dissipated as the wave travels through the wall), there is also a transmitted part of the wave, that is now in your house. (this change of medium will be the third event). Now only the lower frequencies survive, this is why the sound is "muffled".
Those remaining frequencies now travel in your house, and when they reach your ear, your ear sends a signal to your brain and your brain interprets them as sound. The wave interacting with your ear will be the fourth and last mechanical energy event.
Stars having less mass collapses early than those with more mass. This can be explained by Einstein's equation E=mc².
According to this equation, mass of stars is converted into light due to thermonuclear reactions occuring in the core of star which acts as engine of the stars. This thermonuclear reactions keeps star alive. Thermonuclear reactions occurs slowly in massive stars hence massive stars live more than light stars.
a) 0.94 m
The work done by the snow to decelerate the paratrooper is equal to the change in kinetic energy of the man:
where:
is the force applied by the snow
d is the displacement of the man in the snow, so it is the depth of the snow that stopped him
m = 68 kg is the man's mass
v = 0 is the final speed of the man
u = 55 m/s is the initial speed of the man (when it touches the ground)
and where the negative sign in the work is due to the fact that the force exerted by the snow on the man (upward) is opposite to the displacement of the man (downward)
Solving the equation for d, we find:
b) -3740 kg m/s
The magnitude of the impulse exerted by the snow on the man is equal to the variation of momentum of the man:
where
m = 68 kg is the mass of the man
is the change in velocity of the man
Substituting,
Linear momentum has to be conserved. It was zero before the thread eas burned ... when nothing was moving ... so the momentum of the masses moving in opposite directions has to add up to zero. ... Momentum = mass times speed. ... In one direction, you have 5 kg times 1/5 m/s= 1 kg-m/s. ... We need 1 kg-m/s in the other direction. ... 7 kg times speed = 1 kg-m/s. ... Can you finish it from here ?
Because of symmetry electric field component in the x axis cancels out. Now just use electric field formula and slap that sine of theta cause you want the vertical component of electric field and multiply that by two since there’s two charges. I’ve shown my work. Hope it helps✌
