Answer with Explanation:
We are given that
Constant speed of Jane=12.6 m/s
a.When Fred can throw the ball 30 m/s
We have to find the angle relative to the horizontal when he throw the ball in order for Sue to see the ball travel vertically upward.
Let
be the angle .
Therefore,



b.We have to find the height to which ball reach.



Answer:

Explanation:
Ok, the average speed can be calculate with the next equation:
(1)
Basically the car cover the same distance "d" two times, but at different speeds, so:

and the total time would be the time t1 required to go from A to B plus the time t2 required to go back from B to A:

From basic physics we know:

so:


Using the previous information in equation (1)

Factoring:
(2)
Finally, replacing the data in (2)

Answer:
By a factor of 3
Explanation:
In the photon energy formula , frequency and the energy content have a direct relationship. This means anything that is done to one of the parameters is the same that will be done to the other to have a balance.
In this equation: Energy=plank’s constant * frequency.
Energy is directly proportional to frequency.
Answer:
b
Explanation:
i took the quiz i think its right
Plasma...I believe is always a good conductor of electricity. I was tempted to say a solid, but not all solids are the same in composition and that goes for liquid and gas as well.
Hopefully this helped and good luck.