Question

Four charges are arranged at the corners of a regular tetrahedron (a pyramid with four sides that are identical equilateral triangles). The charges are 1 Coulomb each, and the sides of the tetrahedron are all 1 meter. How much energy in Joules is required to assemble this arrangement of charge

Answer 1

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Answer 2

Thank you very much

Answer 3

An insulating sphere of mass m and positive charge q is attached to a spring with length h and spring constant ks and is at equilibrium as shown below:


An infinitely long wire with positive linear charge density λ is placed a distance l away from the charged mass at equilibrium as shown below (note that the position of the top of the spring is fixed):


The previous length of the spring was h. What is the new length of the spring in terms of h, q, ke (type "ke"), λ (type "lambda"), l, and ks (type "ks") as needed. Indicate multiplication with a "*" sign and division with a "/" sign. HINT: You can do this without considering the mass or gravitational force.

length of the spring = ???