Answer:
a) 
b) 
Explanation:
Given:
- upward acceleration of the helicopter,

- time after the takeoff after which the engine is shut off,

a)
<u>Maximum height reached by the helicopter:</u>
using the equation of motion,

where:
u = initial velocity of the helicopter = 0 (took-off from ground)
t = time of observation


b)
- time after which Austin Powers deploys parachute(time of free fall),

- acceleration after deploying the parachute,

<u>height fallen freely by Austin:</u>

where:
initial velocity of fall at the top = 0 (begins from the max height where the system is momentarily at rest)
time of free fall


<u>Velocity just before opening the parachute:</u>



<u>Time taken by the helicopter to fall:</u>

where:
initial velocity of the helicopter just before it begins falling freely = 0
time taken by the helicopter to fall on ground
height from where it falls = 250 m
now,


From the above time 7 seconds are taken for free fall and the remaining time to fall with parachute.
<u>remaining time,</u>



<u>Now the height fallen in the remaining time using parachute:</u>



<u>Now the height of Austin above the ground when the helicopter crashed on the ground:</u>



The product of (wavelength) times (frequency) is always the same number ...
the speed of the wave in whatever material it's traveling through. So if the
frequency is increased, then the wavelength must <em><u>de</u></em>crease by the same
factor, in order to keep the product the same.
Answer:
8100W
Explanation:
Let g = 10m/s2
As water is falling from 60m high, its potential energy from 60m high would convert to power. So the rate of change in potential energy is
or 9000W
Since 10% of this is lost to friction, we take the remaining 90 %
P = 9000*90% = 8100 W
Answer: 31.6ft
Explanation:
Check the attachment for the diagram.
According to the right angle triangle AEC, we will use Pythagoras theorem to get |AC|. Note that |AE| = |AB| - |CD|
that is 20ft - 10ft = 10ft
According to the theorem, the square of the sum of the adjacent side and the opposite side is equal to the square of the hypotenuse.
|AE|^2 + |EC|^2 = |AC|^2
10^2 + 30^2 = |AC|^2
100 + 900 = |AC|^2
|AC| = √1000
|AC| = 31.6ft
Therefore, the wire should be anchored 31.6ft to the ground to minimize the amount of wire needed.