Kepler's three laws of planetary motion can be stated as follows: (1) All planets move about the Sun in elliptical orbits, having the Sun as one of the foci. (2) A radius vector joining any planet to the Sun sweeps out equal areas in equal lengths of time.
R=ρ l/a
l=5 cm
a=0.10 cm²
ρ=1.77×10∧-6 Ωcm
R=(1.77×10∧-6) ×5/0.10
=8.85 ×10∧-5 Ω
resistance is directly proportional to length and inversly proportional to area of cross section is given by above equation
First of all, we need to calculate the magnetic field generated by the wire at a distance r=3.90 cm=0.039 m, which is given by:
where I=8.60 A is the current. Substituting numbers in the equation, we find
And now we can calculate the force exerted on the electron, which is given by:
where 
is the charge of the electron and 
is its speed. Substituting data in the formula, we find
Distance = speed x time
distance = 116 x 10
distance = 1160 m
