Answer:
c. 2 m/s
Explanation:
The speed of a wave is given by:

where
v is the speed of the wave
f is the frequency
is the wavelength
For the wave in this problem, we have
f = 4 Hz is the frequency
is the wavelength
So, the speed of the wave is

Kinetic energy is related to velocity by:
KE = (1/2)mv^2
solve for mass m
10 = (1/2)m(10)^2
10 = (1/2)m(100)
10= 50m
10/50 = m
1/5 = m
at 20 km/hr
KE = (1/2)(1/5)(20)^2
KE = (1/10)(400)
KE = 40 J
Answer:

Explanation:
Given data:
Mass of the paper clip, 
Kinetic energy, 
Let the velocity of the paper clip when it is thrown be <em>v</em>.
Thus,



(rounding to nearest tenth)
<span>
In layman's term: </span>like charges don't attract while opposite charges do<span>electrostatic forces between point A( which is charged) and point B (which is also charged) are proportional to the charge of point A and point B. </span><span>there is also something else about this law that I don't quite remember.</span>
<span>___________________________________________________</span>
<span />Here is the formula:
<span>F = k x Q1 x Q2/d^<span>2</span></span>
<span>What the formula means:</span>
F=force between charges
Q1 and Q2= amount of charge
d=distance between these two charges
k= Coulombs constant (proportionally constant)
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I think that about covers it and hopefully this helped.