The ball took half of the total time ... 4 seconds ... to reach its highest
point, where it began to fall back down to the point of release.
At its highest point, its velocity changed from upward to downward.
At that instant, its velocity was zero.
The acceleration of gravity is 9.8 m/s². That means that an object that's
acted on only by gravity gains 9.8 m/s of downward speed every second.
-- If the object is falling downward, it moves 9.8 m/s faster every second.
-- If the object is tossed upward, it moves 9.8 m/s slower every second.
The ball took 4 seconds to lose all of its upward speed. So it must have
been thrown upward at (4 x 9.8 m/s) = 39.2 m/s .
(That's about 87.7 mph straight up. Somebody had an amazing pitching arm.)
Remark
When you are asked a question like this, the first thing to do is search out a formula and put some limits on it.
Formula
I = E/R which comes from E = IR. To get to the derived formula, divide both sides by R
E/R = I*R/R
E/R = I
Discussion
This is an inverse relationship. That means that as one goes up the other one will go down.
So in this case you keep E constant and you manipulate R and look at your results for I
Case 1
Let us say that E = 10 volts
Let us also say the R = 10 ohms
I = E/R
I = 10/10
I = 1 ohm
Case Two
Let's raise the Resistance to 100 ohms
E = 10
R = 100
I = 10/100 = 0.1
Conclusion
As the Resistance goes up, the current goes down. Answer: A
They believe the distortions happened when two galaxies collided.
Hope This Helps :)
The scientific revolution is a concept which explains how the developments of science (biology, chemistry, physics and etc.) changed the way we (society) think about nature. I hope this helps! :)
