Answer:
W = 7.06 J
Explanation:
From the given information the spring constant 'k' can be calculated using the Hooke's Law.
Now, using this spring constant the additional work required by F to stretch the spring can be found.
The work energy theorem tells us that the work done on the spring is equal to the change in the energy. Therefore,
![W = U_2 - U_1\\W = \frac{1}{2}kx_2^2 - \frac{1}{2}kx_1^2 = \frac{1}{2}(275.13)[0.29^2 - 0.18^2] = 7.06~J](https://tex.z-dn.net/?f=W%20%3D%20U_2%20-%20U_1%5C%5CW%20%3D%20%5Cfrac%7B1%7D%7B2%7Dkx_2%5E2%20-%20%5Cfrac%7B1%7D%7B2%7Dkx_1%5E2%20%3D%20%5Cfrac%7B1%7D%7B2%7D%28275.13%29%5B0.29%5E2%20-%200.18%5E2%5D%20%3D%207.06~J)
Answer:
Explanation:
a)
Ff = μmgcosθ
Ff = 0.28(1600)(9.8)cos(-84)
Ff = 458.9217...
Ff = 460 N
b) ignoring the curves required at top and bottom which change the friction force significantly, especially at the bottom where centripetal acceleration will greatly increase normal forces and thus friction force.
W = Ffd
W = 458.9217(-49.4/sin(-84)
W = 22,795.6119...
W = 23 kJ
c) same assumptions as part b
The change in potential energy minus the work of friction will be kinetic energy.
KE = PE - W
½mv² = mgh - (μmgcosθ)d
v² = 2(gh - (μgcosθ)(h/sinθ))
v = √(2gh(1 - μcotθ))
v = √(2(9.8)(49.4)(1 - 0.28cot84))
v = 30.6552...
v = 31 m/s
Answer:
Astronomers have divided the eight planets of our solar system into the inner planets and the outer planets. The 4 inner planets are the closest to the Sun, and the outer planets are the other four – Jupiter, Saturn, Uranus, and Neptune. The outer planets are also called the Jovian planets or gas giants.
Explanation:
Answer:
Resistance to electrical currents
Explanation:
Conductors have low resistance to electrical currents, and are used to "conduct" the flow of electricity.
Insulators have very high resistance and are used to protect us from the flow of electricity.
<u>Answer:</u>
<em>The initial distance between the trains is 1450 m.
</em>
<u>Explanation:</u>
In the question two trains are of equal length 400 m and moves at a uniform speed of 72 km/h. train A is moving ahead of train B. If the train B has to overtake train A it should accelerate.
Train B’s acceleration is 
and it accelerated for 50 seconds.
<em>
</em>
<em>t=50 s
</em>
<em>initial speed u=72km/h
</em>
<em>we have to convert this speed into m/s </em>
<em>
</em>
<em>Distance covered in accelerating phase 
</em>
<em>
</em>
<em>
</em>
If a train is just behind another, the distance covered by the train located behind during overtaking phase will be equal to the sum of the lengths of the trains.
<em>Here length of train A+length of train 
</em>
<em>Hence the initial distance between the trains = 
</em>
