Answer:
The workdone by Jack is 
The workdone by Jill is 
The final velocity is 
Explanation:
From the question we are given that
The mass of the boat is 
The initial position of the boat is 
The Final position of the boat is 
The Force exerted by Jack 
The Force exerted by Jill 
Now to obtain the displacement made we are to subtract the final position from the initial position


Now that we have obtained the displacement we can obtain the Workdone
which is mathematically represented as
The amount of workdone by jack would be

![= [(-420\r i +0\r j +210\r k)(2\r i + 0\r j - \r k)]](https://tex.z-dn.net/?f=%3D%20%5B%28-420%5Cr%20i%20%2B0%5Cr%20j%20%2B210%5Cr%20k%29%282%5Cr%20%20i%20%2B%200%5Cr%20j%20-%20%5Cr%20k%29%5D)



The amount of workdone by Jill would be

![= [(180 \r i + 0\r j + 360\r k)(2\r i +0\r j -\r k)]](https://tex.z-dn.net/?f=%3D%20%5B%28180%20%5Cr%20i%20%2B%200%5Cr%20j%20%2B%20360%5Cr%20k%29%282%5Cr%20i%20%2B0%5Cr%20j%20-%5Cr%20k%29%5D)


According to work energy theorem the Workdone is equal to the kinetic energy of the boat
![W = K.E = \frac{1}{2} m *[v^2 - (1.1)^2]](https://tex.z-dn.net/?f=W%20%3D%20K.E%20%3D%20%5Cfrac%7B1%7D%7B2%7D%20m%20%2A%5Bv%5E2%20-%20%281.1%29%5E2%5D)
![-1050 = 0.5*3300 [*v^2- (1.1)^2]](https://tex.z-dn.net/?f=-1050%20%20%3D%200.5%2A3300%20%5B%2Av%5E2-%20%281.1%29%5E2%5D)
![-1050 = 1650 [v^2 -1.21]](https://tex.z-dn.net/?f=-1050%20%3D%201650%20%5Bv%5E2%20-1.21%5D)




Answer:
50m; 0m/s.
Explanation:
Given the following data;
Initial velocity = 20m/s
Acceleration, a = - 4m/s²
Time, t = 5secs
To find the displacement, we would use the second equation of motion;

Substituting into the equation, we have;



S = 50m
Next, to find the final velocity, we would use the third equation of motion;
Where;
- V represents the final velocity measured in meter per seconds.
- U represents the initial velocity measured in meter per seconds.
- a represents acceleration measured in meters per seconds square.
<em>Substituting into the equation, we have;</em>
V = 0m/s
<em>Therefore, the displacement of the bus is 50m and its final velocity is 0m/s.</em>
Person standing on A will hear the loudest sound
Explanation:
The intensity of a sound wave (which is proportional to the loudness of the sound) follows an inverse square law, which is:

where
I is the intensity of the wave
r is the distance from the source of the sound
This equation means that the intensity of the sound wave (and therefore, its loudness) is inversely proportional to the square of the distance from the source: therefore,
- As we get closer to the source of sound, the loudness increases
- As we move away from the source of sound, the loudness decreases
Therefore, the person that will hear the loudest sound is the one standing closer to the source, and therefore person A.
Learn more about sound waves:
brainly.com/question/4899681
#LearnwithBrainly
2.496 HZ is the resistance change the resonant frequency.
Given, Supply frequency, f = 60 12
number of poles, P = 4
Full load speed, Ne= 1725 rpm
Synchronous speed; No= 1201= 120X60 = 1800 rpm
P
4
We know the formula for Full load-speed
Ne = N's (1 - Sf)
where se = full load rotor ship
Ne = 1 - SP
SQ = 1- Ne = 1- 1725 = 0.0416 DY 4-16%
1800
SQ= 4. 16 % or 0.0416
Frequency of rotor, fy= Sgif = (0.0416) ( 60 ) = 2.496 Hz
fr = 2.496 HZ
Learn more about Frequency here: brainly.com/question/16148316
#SPJ4