three identical charges q form an equilateral triangle of side a, with two charges on the x-axis and one on the positive y-axis (a) find an expression for the electric field at points on the y-axis above the uppermost charge. (b) show that your result reduces to the field of a point charge 3q for y> > a. 2y [answers: ka j (b) show that 2 3a 4

Engineers find a new metal that is stronger than steel but much lighter. this material is also significantly cheaper than what is currently used for most aircraft, available in large quantities, and easy to manufacture. the engineers are excited because this new material will lower the costs of buying and operating airplanes for companies. what is probably the best step for the engineers to make next?