Answer:
3000 J
Explanation:
Kinetic energy is:
KE = ½ mv²
If m = 15 kg and v = -20 m/s:
KE = ½ (15 kg) (-20 m/s)²
KE = 3000 J
Answer:
The answer is A sorry if i'm wrong
Explanation:
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>



Answer:
Following are the solution to this question:
Explanation:
Law:




Answer:
1 bright fringe every 33 cm.
Explanation:
The formula to calculate the position of the m-th order brigh line (constructive interference) produced by diffraction of light through a diffraction grating is:

where
m is the order of the maximum
is the wavelength of the light
D is the distance of the screen
d is the separation between two adjacent slit
Here we have:
is the wavelength of the light
D = 1 m is the distance of the screen (not given in the problem, so we assume it to be 1 meter)
is the number of lines per mm, so the spacing between two lines is

Therefore, substituting m = 1, we find:

So, on the distant screen, there is 1 bright fringe every 33 cm.