To solve this problem we will apply the concepts related to energy conservation. From this conservation we will find the magnitude of the amplitude. Later for the second part, we will need to find the period, from which it will be possible to obtain the speed of the body.
A) Conservation of Energy,


Here,
m = Mass
v = Velocity
k = Spring constant
A = Amplitude
Rearranging to find the Amplitude we have,

Replacing,


(B) For this part we will begin by applying the concept of Period, this in order to find the speed defined in the mass-spring systems.
The Period is defined as

Replacing,


Now the velocity is described as,


We have all the values, then replacing,


Explanation:
It is given that,
Mass of a bungee jumper is 65 kg
The time period of the oscillation is 38 s, hitting a low point eight more times.It means its time period is

After many oscillations, he finally comes to rest 25.0 m below the level of the bridge.
For an oscillating object, the time period is given by :

k = spring stiffness constant
So,

When the cord is in air,
mg=kx
x = the extension in the cord

So, the unstretched length of the bungee cord is equal to 25 m - 5.6 m = 19.4 m
The ions are in fixed positions.
Explanation:
Ionic solids are poor conductors of electricity because their ions are fixed in position. Their ions are not free to move about. They are fixed in crystal lattices.
- For the conduction of electricity, compounds must possess free mobile electrons and moving ions in solution.
- Ionic compounds are formed by the electrostatic attraction between a metallic and non-metallic ion.
- They actually contain ions but their ions are locked up.
- They are not free to move about.
- Electrical conduction involves ion mobility.
- In molten and aqueous forms, they are able to conduct electricity because their ions are then mobile.
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Because it does not produce waste, thus it doesn't harm the environment. also renewable sources are infinite.