The electric field between the plates of a parallel-plate capacitor is horizontal, uniform, and has a magnitude E. Asmall object with a charge of -2.16 μC is attached to the string. The tension in the string is 0.420 N , and the angle it makes with the vertical is 16 ∘.What is the mass of the object?

Respuesta :

Answer:

[tex]m = 0.041 kg[/tex]

Explanation:

As we know that the small particle is in equilibrium at an angle of 16 degree with the vertical

so here we can use force balance in vertical and horizontal direction

[tex]T cos\theta = mg[/tex]

[tex]T sin\theta = qE[/tex]

now from above equation we have

[tex]T = \sqrt{(mg)^2 + (qE)^2}[/tex]

also by division of above two equations we have

[tex]\frac{qE}{mg} = tan\theta[/tex]

[tex]qE = mg tan\theta[/tex]

now from above equation again

[tex]T = \sqrt{(mg)^2 + (mg)^2 tan^2\theta}[/tex]

[tex]T = mg sec\theta[/tex]

[tex]0.420 = m(9.81) sec 16[/tex]

[tex]m = 0.041 kg[/tex]