Everyone knows that one of their favorite past times is sitting in front of the television and watching movies, shows, or playing video games. However with this almost motionless, lazy activity comes a great deal of static physics and mechanics.
When you are sitting down enjoying whatever show it is you may be watching, you actually have several forces acting on you concurrently. For example, by sitting on the couch with no extra weight on you, your weight is equivalent to the normal force, or the force of the couch on you. In addition to the force of the couch of you, if you are leaning on an arm or laying down, a similar force acts on you, except at an angle or incline. The general rule for laying on the couch watching television is that whatever force you exert on an object, that object exerts the same force in the opposite direction, or 180 degrees around.
Answer:
588 J
Explanation:
PE (potential energy) = (mass) x (gravity) x (height)
mass = 12 kg
gravity = 9.8m/s^2
height = 5 m
PE = (12) x (9.8) x (5) = 588 J (Joules)
Answer:
The correct answer is theory of general relativity.
Explanation:
According to the statement of equivalence the gravitational mass force on an object standing on the surface of earth is same as the pseudo force that acts on it if it accelerated at acceleration equal to acceleration due to gravity.
According to Einestine both the forces are indistinguishable as both the forces produce same effects. Thus both are equivalent and thus gravity is a phenomenon that can be analysed in a radically different way which gives some strange results such as bending of light, existence of black holes,e.t.c
Answer:
Approximately 
to the right (assuming that both astronauts were originally stationary.)
Explanation:
If an object of mass 
is moving at a velocity of 
, the momentum 
of that object would be 
.
Since momentum of this system (of the astronauts) conserved:
.
Assuming that both astronauts were originally stationary. The total initial momentum of the two astronauts would be 
since the velocity of both astronauts was 
.
Therefore:
.
The final momentum of the first astronaut (
, 
to the left) would be 
to the left.
Let 
denote the momentum of the astronaut in question. The total final momentum of the two astronauts, combined, would be 
.
.
Hence, 
. In other words, the final momentum of the astronaut in question is the opposite of that of the first astronaut. Since momentum is a vector quantity, the momentum of the two astronauts magnitude (
) but opposite in direction (to the right versus to the left.)
Rearrange the equation to obtain an expression for velocity in terms of momentum and mass: 
.
.
Hence, the velocity of the astronaut in question (
) would be to the right.
