Answer:
Explanation:
Work done by the spring is negative .
Work done by force F creating displacement d is given by the following expression .
Work = F x d
Both force and displacement are vector quantity .
When direction of force and direction of displacement is same , work is positive . When direction of force and direction of displacement is opposite , work is negative .
When spring is compressed , it exerts a restoring or opposing force in a direction opposite to the direction of displacement of box . Hence here force is opposite to displacement . Restoring force acts opposite to displacement . Hence work done by spring on box is negative .
This is another one of those muddy misleading questions, followed by
a muddy group of choices from which an answer must be selected.
a). is absurd. There's no such thing as a "balanced force", only
a balanced group of forces.
b). is probably the choice the question is aiming for.
c). is not so. The engines of an airplane do plenty of work lifting the plane
off the ground, although the force of the engines is never directed upward.
d). is really awkward. The object's motion is almost never the cause of the force.
The force is almost always the cause of the object's motion.
Now for the big 800-lb gorilla in the room: No moving object needs to be involved
in order for energy to be flowing or work to be getting done.
-- A radio wave radiates through space. Straighten out a wire coat-hanger and
stick it up in the air where the radio wave can pass by it. Electrical current flows
through the wire, and you can drain the electrical energy out the bottom of it.
-- A light bulb is shining. Some distance away, something it's shining on
gets warm, because of the heat energy that has shot across to it from the
light bulb and soaked into it.
-- A lightning bolt jumps from the ground to a passing cloud. Or, if you feel
more comfortable with it, a lightning bolt jumps from a cloud to the ground.
It doesn't matter. Either way, there's enough energy splashing around to
ignite houses, zap TVs and computers, melt concrete, vaporize water, and
light up a city. Although nothing is moving.
Known variables
d=4.6m
initial velocity=0m/s
downward acceleration=-9.8m/s2
d=1/2gt2
4.6=1/2 -9.8 t2
t=0.93s
Answer:
Because each color is refracted differently, each bends at a different angle, resulting in a fanning out and separation of white light into the colors of the spectrum.
C stands for carbon. The O stands for oxygen. CO2 is one carbon atom and two oxygen atoms
