A uniform horizontal wire with a linear mass density of 0.52 g/m carries a 1.7 A

Question

A uniform horizontal wire with a linear mass density of 0.52 g/m carries a 1.7 A current. It is placed in a constant magnetic field with a strength of 3.50 10-3 T. The field is horizontal and perpendicular to the wire. Neglect the magnetic field of the Earth.
(a) As the wire moves upward starting from rest, what is its acceleration?
1.64 m/s2

(b) How long does it take to rise 50 cm?
s

I equaled Fnet = Fmagnetic
F= ma= BLI (for mag field wire)
Attempted to solve for a = BLI/m
Length gets cancelled because mass density is given in g/m
a= ((3.5e-3)(1.7A)) / .00052 kg = 11.4 m/s2 which is wrong :(
I would love to know how to solve the two parts correctly. Thank you!

Explanation / Answer

for part a you forgot to take into account the force due to gravity so your force equation should be F=ma=BLI-mg, then as you said divide by m which is equal to mdensityL so you can now rewrite the equations as mdensityLa=L(BI-mdensityg) then a=(BI-mdensityg)/mdensity which becomes a=((3.5E-3)(1.7)-(9.8)(.00052))/.00052 so a becomes 1.64 m/s2.

then to find time you use simple kinematics using equation t=((2y)/a) after plugging everything in you get time to be .78 seconds

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