<span>Four waste materials from copper ore processing are: ore minerals, unwanted rock or gangue, uranium, and pyrite/sulfide minerals. Ore minerals are contained in rock and have potential to be economically extracted, gangue may contain silicate minerals for which there is no economic value, uranium is a frequently-occurring radionuclide found in ore bodies, and pyrite and sulfide minerals may be found in tailings piles during copper processing.</span>
Answer:
The magnitude of the force exerted by the ball on the catcher is 1.9 × 10² N
Explanation:
Hi there!
Let´s find the acceleration of the ball that makes it stop when caught by the catcher. The acceleration can be calculated from the equation of velocity considering that it is constant:
v = v0 + a · t
We know that initially the ball was traveling at 25 m/s, so, if we consider the position of the catcher as the origin of the frame of reference, then, v0 = -25 m/s. We also know that it takes the ball 20 ms (0.02 s) to stop (i.e. to reach a velocity of 0). Then using the equation of velocity:
v = v0 + a · t
0 m/s = -25 m/s + a · 0.020 s
25 m/s/ 0.020 s = a
Now, using the second law of Newton, we can calculate the force exerted by the catcher on the ball:
F = m · a
Where:
F = force.
m = mass of the ball.
a = acceleration.
F = 0.150 kg · (25 m/s/ 0.020 s) = 1.9 × 10² N
According to Newton´s third law, the force exerted by the ball on the catcher will be of equal magnitude but opposite direction. Then, the force exerted by the ball on the catcher will have a magnitude of 1.9 × 10² N.
Answer: 0.016 h
Explanation:

It is given that, biker has an average speed = 18 km/h
Total distance traveled = 0.30 km
Therefore, time taken by biker to travel this distance:

Thus, the biker takes 0.016 hours to travel the segment of 0.30 km at an average speed of 18 km/h.
Answer:
Heat energy does not cool. Objects cool. Energy is not an object. Now, what happens when an object cools is that it gives off some of its thermal energy by one or more mechanisms: radiation, conduction, or convection. In radiation the energy escaped the object as electromagnetic waves - you see the red hot poker slowly dim as it cools, in conduction the energy is transferred Mechanically by the atoms of the hot object being in physical contact with those of the cool object and in convection the hot material moves to a cooler region where it gives up its heat energy by either radiation or conduction.