In establishing standing waves with a slinky®, your wrist oscillates with f frequency of 4.0 hz, and the length between any two consecutive nodes is 2.5 meters. what is the velocity of the wave generated?
v = m/s
20.
10.
1.6
0.80

Find an expression for the electric field e⃗ at the center of the semicircle. hint: a small piece of arc length δs spans a small angle δθ=δs /r, where r is the radius. express your answer in terms of the variables q, l, unit vectors i^, j^, and appropriate constants.