We have that the Velocities is mathematically given as
a)v=2.8e5m/s
b)v_2=3.11e5m/s
From the question we are told
Generally the equation for the workdone is mathematically given as
a)
[tex]-qEr=0.5m(u/2)^2\\\\Therefore\\\\1.6e-19*19*2.9e-3=0.5*9.1e-31*v^2/4[/tex]
v=2.8e5m/s
b)
applying work
[tex]-qEr=0.5m(u/2)^2\\\\1.6e-19*19*2.9e-3=0.5*9.1e-31(v_2^2-7.75e10)[/tex]
v_2=3.11e5m/s
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