Answer:
Explanation:
In a frictionless system with no acceleration, the tension in the rope must be F along its entire length
FBD analysis of the lower pulley has two upward acting tension vectors F and one downward acting weight vector W
2F = W
F = W/2
FBD analysis of the upper pulley has one upward acting support vector T and three downward acting tension vectors F
T = 3F
T = 3(W/2)
T = 1.5W
Traveling at any point on a curve, the force and the acceleration are toward
the center of the circle that the curve is part of. On a perfectly circular path,
the force and acceleration are always toward the center of the circle.
During a chemical reaction, atoms react with each other to form new products. hope this helps (:
Sound waves can travel through ANY material ... solid, liquid, or gas.
The thing is: Sound NEEDS material to travel through, and if there's
nothing there, then sound can't go anywhere. The correct choice
on the list is 'D' ... Sound can't travel through vacuum, because
there's nothing there. When we talk to each other, the AIR between
us carries the sound waves.
Have you ever seen any video of two astronauts standing on the
moon, or two astronauts "space-walking" on the outside of the
Space Shuttle ?
Naturally, they have their helmets on, and they're talking to
each other. How are they talking ? No matter how close together
they are, they're talking to each other by radio ! because there's
nothing between them to carry sound. Even if they're only a few
inches apart, they can SHOUT but the other one can't hear it.
I have read ... I don't think there's any video of this ... that sometimes
when two astronauts are very close together, they can talk if they
touch their helmets together. Then the sound vibrations can go from
one helmet over to the other one, through the solid shell of the helmets.
