This is where we have to admit that gravitational potential energy is
one of those things that depends on the "frame of reference", or
'relative to what?'.
Potential energy = (mass) x (gravity) x (<em>height</em>).
So you have to specify <em><u>height above what</u></em> .
-- With respect to the ground, the ball has zero potential energy.
(If you let go of it, it will gain zero kinetic energy as it falls to
the ground.)
-- With respect to the floor in your basement, the potential energy is
(3) x (9.8) x (3 meters) = 88.2 joules.
(If you let go of it, it will gain 88.2 joules of kinetic energy as it falls
to the floor of your basement.)
-- With respect to the top of that 10-meter hill over there, the potential
energy is
(3) x (9.8) x (-10) = -294 joules
(Its potential energy is negative. After you let go of it, you have to give it
294 joules of energy that it doesn't have now, in order to lift it to the top of
the hill <em>where it will have zero</em> potential energy.)
Answer:
24,187.04 J ≈ 24,200 J
Explanation:
mass (m) = 544 kg
initial speed (u) = 6.75 m/s
final speed (v) = 15.2 m/s
change in height (Δh) = -14 m (negative sign is because there is a decrease in height )
acceleration due to gravity (g) = 9.8 m/s^{2}
How much work was done on the raft by non conservative forces?
work done = change in energy of the system = change in kinetic energy + change in potential energy
work done = (
) + (mgΔh)
work done = (
) + (544 x 9.8 x (-14))
work done = 50449.76 - 74,636.8
work done = 24,187.04 J ≈ 24,200 J
Force is the ability to cause masses to accelerate.
Without force, you could not make stuff accelerate.
If something was moving, you could not make it speed up, slow down, stop, or go in a different direction.
If a thing was not moving, you could not make it move at all.
Answer:
0.195 m
Explanation:
Speed is distance moved per unit time, expressed as s=d/t and making d the subject of the formula then d=st
Where d is distance/depth moved, s is rhe speed of waves and t is time in seconds.
Substituting s with 1300 m/s and t with 0.00015 s then the depth of metal segment will be
D=1300*0.00015=0.195 m
Therefore, the depth is equivalent to 0.195 m
