Ametal foil has a threshold frequency of 5.45×1014 hz . which of the colors of visible light have enough energy to eject electrons from this metal?

4. who was the first one to measure the speed of light and conclude that it is finite? 5. who was the first philosopher who thought the speed of light is finite? 13. what is the speed of light numerically? 14. give an example of something moving faster than light 15. give an example for some particles or waves that

Intro: a solid ball of radius rb has a uniform charge density ρ. part a: what is the magnitude of the electric field e(r) at a distance r> rb from the center of the ball? express your answer in terms of ρ, rb, r, and ϵ0. part b: what is the magnitude of the electric field e(r) at a distance r express your answer in terms of ρ, rb, r, and ϵ0. part c: let e(r) represent the electric field due to the charged ball throughout all of space. which of the following statements about the electric field are true? check all that apply. e(0) = 0 e(rb)=0 limr→∞e(r)=0 the maximum electric field occurs when r=0 the maximum electric field occurs when r=rb the maximum electric field occurs as r→∞.

Check the following equation for dimensional homogeneity: ⅆ mv=∫t1t2(f⁢cosθ)ⅆt where m is mass, v is velocity, f is force, θ is an angle, and t is time. check that each term in the equation has the following dimensions: [malbec] where you are to choose the coefficients a, b, c.