Stevie asked in Science & MathematicsPhysics · 8 months ago

# Physics electric charges! Can you help?

Two tiny conducting spheres are identical and carry charges of -17.2C and +53.8C. They are separated by a distance of 2.34 cm. (a) What is the magnitude of the force that each sphere experiences? (b) The spheres are brought into contact and then separated to a distance of 2.34 cm. Determine the magnitude of the force that each sphere now experiences.

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• 8 months ago

F = (9e9)(17.2)(53.8) / (0.0234)² = 1.52e16 N (same for both)

(strange problem as that force is huge, enough to lift about 50 mountains)

in contact, 17.2 of negative charge cancels 17.2 of + charge, leaving total charge of 36.6 C

IF the two spheres are identical, then they separate, they each get half or 18.3 C

F = (9e9)(18.3)(18.3) / (0.0234)² = 5.50e15 N (same for both)

Coulomb's law, force of attraction/repulsion

F = kQ₁Q₂/r²

Q₁ and Q₂ are the charges in coulombs

F is force in newtons

r is separation in meters

k = 8.99e9 Nm²/C²