If you measured all the energy related to motion and all the stored
energy in the particles of a substance, you would be measuring the thermal energy of the particles. If
there is movement of the particles, they are also releasing energy in the form
of heat.
There are at least two forces on it, and there could be more.
Vertical forces:
-- gravity, directed downward
-- buoyant force, directed upward
These two forces must be exactly equal, so that the net
vertical force on the raft is zero. Otherwise, it would be
accelerating either up or down.
Horizontal forces:
We know that the net horizontal force on the raft is zero.
Otherwise, it would be accelerating horizontally.
But we don't know if there are actually no horizontal forces
at all, or a balanced group of horizontal forces, that add up
to a net force of zero.
Answer:
d) is the same as when it started from rest
Explanation:
using equation of motion
v = u + at
second law of momentum defines
F = ma
a = F /m
the equation becomes
v = u + (F/m)t
from hear
since v is directly proportional to the force and the force remain the same, the increase in the cart speed will also remain the same.
Explanation:
The volume of the bread decreases, making the bread appear more compact, and smaller in size. The mass stays the same, it won't change unless part of the bread is removed. The density increases, the air bubbles inside of the bread get squished down, causing the bread to be smaller, and in turn, causing it to be more solid.
I hope this helped!
Thanks!
Your friend in answering,
~Steve
