Potential energy is energy due to an object's height above the ground.
Potential energy = mass x gravity x height
Kinetic energy is energy due to the motion of the object.
Kinetic energy = 1/2 x mass x velocity²
1.
The ball is not moving and is at a height above the ground so it has only potential energy.
P.E = 2 x 9.81 x 40
P.E = 784.8 J
2.
The ball is moving and has a height above the Earth's surface so it has both kinetic and potential energy.
P.E = same as part 1 = 784.8 J
K.E = 1/2 x 2 x 5²
K.E = 25 J
3.
The ball has no height above the Earth's surface and is moving so it has only kinetic energy.
K.E = 1/2 x 2 x 10²
K.E = 100 J
4.
50000 = 1/2 x 1000 x v²
v = 10 m/s
5.
39200 = 200 x 9.81 x h
h = 20.0 m
6.
12.5 = 1/2 x 1 x v²
v = 5 m/s
98 = 1 x 9.81 x h
h = 10.0 m
Answer:
2: Moved faster and spread farther apart.
Explanation:
Restate the question: The movement of the liquid in a thermometer shows changes in temperature. An increase in temperature indicates the molecules in the liquid.
1. moved slower and closer together.
2.moved faster and spread farther apart.
3. contracted in size when heated.
4. expanded in size when heated.
Water that is cold does not have the energy to bounce of the walls, instead it is like a group of animals they group together for the warmth of the others when it gets really cold.
So it cant be 1.
We all know that power lines sag lower on a hot day (or a tire for a car, it has increases pressure). but those are different types of molecules.
So that rules out 3 and 4.
Which leaves you with 2.
The increase in temperature causes the water molecule to gain energy and move quickly, which resulted in water molecule that are farther apart and an increase in water volume.
Hope it helps!
Answer:
c,e,f
Explanation:
Judging by what i tried to find out about this reaction, it seems that won't take place, though it could be wrong.
A mole of magnesium is the number of gra ms of magnesium corresponding to its mass numbers
I believe the answer is A. <span>make a softer sound because the shark will not hear the softer signal.
</span><span>
I say this becasue "</span><span>Some of the sounds dolphins make are outside the range of human hearing." So that means the the dolphins speak at a higher wavelength then us humans and we can't hear it so they could use that to their advantage and speak at a height wavelength to each other when sharks are near.
I could be wrong, but I think the answer is A. </span>
