Answer: W = 0.3853 J, e = 0.052 m
Explanation: Given that,
K =285.0N/M , L = 0.230m , F = 15N , e = ?
F = Ke
15 = 285 × e
e = 15÷ 285
e =0.052 m
e + L = 0.052 + 0.230
= 0.282m ( spring new length )
Work needed to stretch the spring
W = 1/2ke2
W = 1/2 × 285 x 0.052 × 0.052
W = 0.3853 J
For both NPN and PNP this is true:
The base is between the collector and the emitter.
<span>Folded mountains form because two tectonic plates move towards each other at a convergent plate boundary pushing the land up forming a mountain.
Hope this helps!!
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The time after being ejected is the boulder moving at a speed 20.7 m/s upward is 2.0204 s.
<h3>What is the time after being ejected is the boulder moving at a speed 20.7 m/s upward?</h3>
The motion of the boulder is a uniformly accelerated motion, with constant acceleration
a = g = -9.8 
downward (acceleration due to gravity).
By using Suvat equation:
v = u + at
where: v is the velocity at time t
u = 40.0 m/s is the initial velocity
a = g = -9.8
is the acceleration
To find the time t at which the velocity is v = 20.7 m/s
Therefore,

The time after being ejected is the boulder moving at a speed 20.7 m/s upward is 2.0204 s.
The complete question is:
A large boulder is ejected vertically upward from a volcano with an initial speed of 40.0 m/s. Ignore air resistance. At what time after being ejected is the boulder moving at 20.7 m/s upward?
To learn more about uniformly accelerated motion refer to:
brainly.com/question/14669575
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The colors that you see on the CD are created by white light reflecting from ridges in the metal. When light reflects off or passes through something with many small ridges or scratches, you often get rainbow colors and interesting patterns. They are called interference patterns.