Answer:

Explanation:
Using the conservation of energy we have:

Let's solve it for v:

So the speed at the lowest point is 
Now, using the conservation of momentum we have:

Therefore the speed of the block after the collision is 
I hope it helps you!
Answer:
Oppositely charged particles attract each other, while like particles repel one another. Electrons are kept in the orbit around the nucleus by the electromagnetic force, because the nucleus in the center of the atom is positively charged and attracts the negatively charged electrons.
Explanation:
If the compressor removes 500 j if the 700 the 200 j left would have Ben conducted through the refrigerator/200 j released into the room
Answer:
Angular acceleration, 
Explanation:
It is given that,
Mass of the solid sphere, m = 245 g = 0.245 kg
Diameter of the sphere, d = 4.3 cm = 0.043 m
Radius, r = 0.0215 m
Force acting at a point, F = 0.02 N
Let
is its angular acceleration. The relation between the angular acceleration and the torque is given by :

I is the moment of inertia of the solid sphere
For a solid sphere, 





So, its angular acceleration is
. Hence, this is the required solution.
Answer:
a) three times greater
Explanation:
Remember the heat capacity is the necessary heat to increase the temperature 1 ºC to an specific mass of the substance, in this case since the water and the metal have the same mass, is easier to compare just the neccesary heat.
Since water increases 20 ºC and the metal 60 ºC, it was neccesary 3 times of the quantity of heat to the same amount of mass of the two different susbtances.
Hope it was useful