Answer:
Speed of the electron will be 
Explanation:
We have given that charge on electron 
Mass of electron 
Potential difference = 
Now according to energy conservation 


The light bulb, it takes electrical energy and turns it into l<span>ight energy!</span>
Ignoring fluid resistance, football will <span>maintain a constant speed until other forces accelerate the football.</span>
Rw^2 = GmM/r^2
<span> Leads to
</span><span> w^2 r^3 = GM
</span><span> (2pi /T) ^2 r^3 = GM
</span><span> 4pi^2 r^3 = GM T^2
</span><span> r^3 = GM T^2 / 4pi^2
</span><span> Work out r^3 then r.
</span> T = 125 min = 125(60) = 7500 s
<span> R = 6.38E6 m
</span><span> m = 5.97E24 kg
</span><span> G = 6.673E-11
</span> r=<span>
8279791.78</span><span> m
Since r = radius R of Earth + height above urface,h
</span><span> h = r - R = </span><span>
8279791.78 - </span>6.38E6 = <span>
<span>1899791.78 m
h=</span></span><span>
<span>1899.79178 Km</span></span>
I believe the answer is 2m/s