Answer:
a)
, b) 
Explanation:
a) The maximum height is obtained with the help of the First and Second Derivative Tests:
First Derivative



Second Derivative
(absolute maximum)
The maximum height reached by the ball is:


b) The time required by the ball to hit the ground is:




Just one root offers a solution that is physically reasonable:

The velocity of the ball when it hits the ground is:


Answer:
Explanation:
Well you have the voltages right, and that is no trivial matter. Each one of the resistors in a parallel circuit sees the same input voltages (in this case 6).
Now I think it would be a good idea to fill in the the resistance column.
R1 = 3 ohms
R2 = 6 ohms
R3 = 2 ohms
The total resistance can be calculated in two ways. I'll get around to doing both of them but I'll do the conventional way first. One hint: the total resistance must be smaller than the smallest resistor. Read that sentence over a couple of times. What it means is that it must be less than 2 ohms in a parallel circuit.
1/r1 + 1/r2 + 1/r3 = 1/rt
1/3 + 1/6 + 1/2 = 1/rt
Change all the denominators to 6ths.
2/6 + 1/6 + 3/6 = 1/rt
(2 + 1 + 3)/6 = 6/6 = 1
rt = 1
====================
So the current I is V/R
V = 6
R = 1
Current = V/R = 6/1 = 6 amps.
====================
The current in each resistor is
I1 = V / R1
I1 = 6/3 = 2 amps
I2 = V/R2
I2 = 6/6 = 1 amp
I3 = 6/2 = 3 amps
The total is I1 + I2 + I3 = 2 + 1 + 3 = 6 amps.
======================
Remember I said there was 2 ways of figuring out the total resistance. I did one of them about. Here's the other.
R = V / It
R = 6 / 6
R = 1 ohm just what you got before.
====================
Power
P = V * I
P1 = 6 * 2 = 12 watts
P2 = 6*1 = 6 watts
P3 = 6*3 = 18 watts
Pt = 36 watts.
Pt can be done by using the voltage * the total current
Pt = 6 volts * 6 amps = 36 watts, just what you would expect.
the first one is octet and the second one is stable
Answer:
F = -3120 N
Explanation:
Lets write out everything we have:
Lineman:
m = 120kg
V1 = 6.5m/s
v2 = 0
t = 0.25
We should find acceleration, to move on to the next step;
a = v2-v1 / t
a = 0 - 6.5 / 0.25
a = -26m/s^2
Now we can use the Fnet formula and solve for F;
Fnet = ma
fnet = (120)(-26)
F = -3120 N