Which of the following is NoT a characteristic of electromagnetic light waves? A. They can’t travel through a vacuum. B. They travel at the same speed through any one material. C. They obey the formula: velocity = wavelength x frequency. D. They can be reflected and refracted.

If jerome is swinging on a rope and transferring energy from gravitational potential energy to kinetic energy, is being done.

Abird flies directly overhead from where you stand at an altitude of 300.0 m and at a speed horizontal to the ground of 20.0 m/s. the bird has a mass of 2.0 kg. the radius vector to the bird makes an angle \thetaθ with respect to the ground. the radius vector to the bird and its momentum vector lie in the xyxy-plane. what is the bird’s angular momentum about the point where you are standing?

Aresistor with an unknown resistance is connected in parallel to a 9 ω resistor. when both resistors are connected in parallel to an emf source of 21 v, the current through the unknown resistor is measured with an ammeter to be 4 a. what is the resistance of the unknown resistor? answer in units of ω.