How can the strength of an electromagnet be increase

What produces light and all other electromagnetic waves? a) the photoelectric phenomena b) heated metals c) charged particles d) radioactive samples (pls explain if you can : )

Afeather of mass 0.001 kg falls from a height of 2 m. under realistic conditions, it experiences air resistance. based on what you know about friction, what can you say about the kinetic energy of the feather as it reaches the ground? acceleration due to gravity is g = 9.8 m/s2. a. ke < 0.0196 j b. ke = 00196 j c. je = 0 j d. ke > 0.0196 j

You have a pick-up truck that weighed 4,000 pounds when it was new. you are modifying it to increase its ground clearance. when you are finished