Answer:
t = 0.437 s
Explanation:
The speed of sound is a constant that is worth v = 343 m / s
v = d / t
t = d / v
the time it takes for the sound to reach Clark at d = 150 m is
t = 150/343
t = 0.437 s
This same sound takes much longer to reach you
t₂ = 127 10³/343
t₂ = 370 s
Answer:
675J
Explanation:
Given parameters:
Force = 45N
Distance = 15m
Unknown:
Work done by Sheila = ?
Solution:
Work done by a body is the amount of force applied to make a body move through a distance;
Work done = Force x distance
Now;
Work done = 45 x 15 = 675J
I believe it is acceleration
Work done by a given force is given by
![W = F.d](https://tex.z-dn.net/?f=W%20%3D%20F.d)
here on sled two forces will do work
1. Applied force by Max
2. Frictional force due to ground
Now by force diagram of sled we can see the angle of force and displacement
work done by Max = ![W_1 = Fdcos\theta](https://tex.z-dn.net/?f=W_1%20%3D%20Fdcos%5Ctheta)
![W_1 = 12*5cos15](https://tex.z-dn.net/?f=W_1%20%3D%2012%2A5cos15)
Now similarly work done by frictional force
![W_2 = Fdcos\theta](https://tex.z-dn.net/?f=W_2%20%3D%20Fdcos%5Ctheta)
![W_2 = 4*5cos180](https://tex.z-dn.net/?f=W_2%20%3D%204%2A5cos180)
![W_2= -20 J](https://tex.z-dn.net/?f=W_2%3D%20-20%20J)
Now total work done on sled
![W_{net}= W_1 + W2](https://tex.z-dn.net/?f=W_%7Bnet%7D%3D%20W_1%20%2B%20W2)
![W_{net} = 57.96 - 20 = 37.96 J](https://tex.z-dn.net/?f=W_%7Bnet%7D%20%3D%2057.96%20-%2020%20%3D%2037.96%20J)
Answer:
Currently in the united states using parallel system
Explanation:
because you can walk with the twomodes with internal combustion engine or running on electric power.