If the distance between two charges is increased to three times the original distance, how will the electrical force between the charges compare with the original force? it will increase to three times the original force. it will increase to nine times the original force. it will decrease to one-third the original force. it will decrease to one-ninth the original force.

It will decrease to one-ninth the original force.

Explanation: Let the two charges be q and q' and distance between them be d. The electric force between the charges would be

when the distance between the charges is increases by the three times, the force would reduce by nine times as the electric force between two charges is inversely proportional to square of the distance between them.

Thus, the correct option is it will decrease to one-ninth the original force.

adding a(n) to an electric circuit would increase the magnetic field around a wire;

b. solenoid

a solenoid is a type of electromagnet whose purpose is to generate a controlled magnetic field.

if the purpose of the solenoid is instead to impede changes in the electric current, a solenoid can be more specifically classified as an inductor rather than an electromagnet.

you'd use the equation that establishes a relationship between  energy  and  wavelength, which looks like this

e=h⋅cλ, where

λ  - the wavelength of the photon; c  - the speed of light, usually given as  3⋅108m/s; h  -  planck's constant, equal to  6.626⋅10−34j s

plug the value you were given for the energy of the photon in the above equation to get the wavelength

e=h⋅cλ⇒λ=h⋅ce

λ=6.626⋅10−34js⋅3⋅108ms−1.257⋅10−24j=1.581⋅10−1m