Electrical force look for my mistake please

AI Thread Summary
The discussion revolves around calculating the net charge on a plastic ball suspended in an electric field, given its mass, string length, and angle with the vertical. The initial formula used for the calculation appears to have a mistake in the angle, which should be 27.6º instead of 24.7º. The correct formula involves the mass, gravitational acceleration, tangent of the angle, and the electric field strength. Participants suggest verifying the angle and recalculating to find the accurate charge in microcoulombs. Ensuring the correct angle is crucial for obtaining the right result.
Number1
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A small 5.48 g plastic ball is suspended by a
24.7 cm long string in a uniform electric field
of 3980 N/C, as shown.The acceleration of gravity is 9.8 m/s2 , and
the Coulomb constant is 8.99×109 N · m2/C2..
If the ball is in equilibrium when the string
makes a 27.6◦ angle with the vertical as indi-
cated, what is the net charge on the ball?
Answer in units of μC.

This is how i did it.

q= m*g*tanz/e
q= 24.7e-3 * 9.81*tan 24.7 / 3980
q= 31.79545474

Please tell me what is wrong or if i am using the wrong formula
 
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Hi Number1! :smile:

(have a degree: º and try using the X2 tag just above the Reply box :wink:)
Number1 said:
q= 24.7e-3 * 9.81*tan 24.7 / 3980

(I haven't checked the rest of your calculation, but …) that 24.7º should be 27.6º. :smile:
 
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