Answer:
it depends on wether the + and - are facing eachother
or away from eachother
Explanation:
Answer:
Option A
Carrots are cut into small pieces and mixed into a salad
Explanation:
When physical changes occur, the actual composition remain the same but the molecules are re-arranged. Therefore, when carrots are cut into smaller pieces and mixed into salad, there will be no chemical reaction hence the actual composition will remain the same despite being cut and molecules in it re-arranged. Considering the other options, new substances are formed hence they are deemed as chemical changes. Therefore, option A is correct.
Answer:
A) The north pole of a bar magnet will attract the south pole of another bar magnet.
B) Earth's geographic north pole is actually a magnetic south pole.
E) The south poles of two bar magnets will repel each other.
Explanation:
<u>According to </u><u>classical physics</u>, a magnetic field always has two associated magnetic poles (north and south), the same happens with magnets. This means that if we break a magnet in half, we will have two magnets, where each new magnet will have a new south pole, and a new north pole.
This is because <u>for classical physics, naturally, magnetic monopoles can not exist. </u>
In this context, Earth is similar to a magnetic bar with a north pole and a south pole. This means, the axis that crosses the Earth from pole to pole is like a big magnet.
Now, by convention, on all magnets the north pole is where the magnetic lines of force leave the magnet and the south pole is where the magnetic lines of force enter the magnet.
Then, for the case of the Earth, the north pole of the magnet is located towards the geographic south pole and the south pole of the magnet is near the geographic north pole.
And it is for this reason, moreover, that the magnetic field lines enter the Earth through its magnetic south pole (which is the geographic north pole).
Answer:2.5 m/s
37.5KJ
Explanation:
Let 
be the initial velocity of rail road car ,coupled cars & Final velocity of system respectively.
Conserving momentum
Therefore Final velocity of system is 2.5m/s
(b)Mechanical Energy lost =Initial Kinetic Energy -Final Kinetic Energy
Answer:
KE_2 = 3.48J
Explanation:
Conservation of Energy
E_1 = E_2
PE_1+KE_1 = PE_2+KE_2
m*g*h+(1/2)m*v² = m*g*h+(1/2)m*v²
(0.0780kg)*(9.81m/s²)*(5.36m)+(.5)*(0.0780kg)*(4.84m/s)² = (0.0780kg)*(9.81m/s²)*(2m)+KE_2
4.10J+0.914J = 1.53J + KE_2
5.01J = 1.53J + KE_2
KE_2 = 3.48J
