The correct answer is A) <span>The two magnetic fields repel each other, causing the train to levitate, or hover, above the rails.
In fact, same magnetic poles repel each other, while opposite magnetic poles attract each other. the magnets on bottom of the train and on top of the railway have the same polarities, so they repel each other and this allows the train to levitate.
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The answer is NOT covalent , it is Hydrogen .
6.08 Trillion electrons = 6.08x10^12
1electron = 1.6x10^-19c
6.08x10^12e × 1.6x10^-19c = 9.728x10-7 coulomb
Answer:
Tension force does no work
78 m/s
55701 J
Explanation:
The work done by the tension force of the rope is the dot product of the tension force vector and the distance travel vector as he swings. However, as these 2 vectors are always perpendicular to each other, their dot product would be 0 (cos(90) = 0). So the work done by tension force is 0.
If we neglect air resistance, then only gravity does work on the swimmer. We can apply the following energy conservation equation to calculate the kinetic energy once we let go of the rope.
where m is the mass of the swimmer, g = 9.81 m/s2 is the gravitational constant, Δh = 415 - 105 = 310 m is the height difference as he swings from horizontal point to the let go point. v is the let go speed. We can divide both sides by m
If the swimmer actually end up with only 67.8 m/s, then the loss in kinetic energy is due to air resistance during the swinging process. We can also find this by calculating the difference between the kinetics energies