Select the correct answer under which of these conditions will no image be formed (real or virtual) for an object placed in front of a concave mirror? a. the object is placed at the focal point on the principal axis. b. the object is placed at the center of curvature on the principal axis. c. the object is placed between the center of curvature and focal point on the principal axis. d. the object is placed between the focal point and the vertex on the principal axis.

Astudent is performing an experiment comparing sound and light waves. the student gathers the following data. what conclusion does the student most likely make based on this data? light waves always travel the same speed; however, the speed of sound is determined by the medium that it travels through. all sound waves always have the same energy, so the temperature of the medium does not affect wave speed. light needs to vibrate particles, so it travels fastest in tightly packed solids, while sound does not need a medium, so it travels fastest in a gas. tightly packed particles in solids slow down the light waves; however, sound waves make particles bounce into each other, so they travel faster in solids.

What tightening torque should be used for a hexagonal head screw (not split-bolt) on a 250 kcmil conductor?

The charge on an electron is 1.60218 × 10−19 c and its mass is 9.10939 × 10−31 kg. how strong a magnetic field must be experienced by the electron if its path is a circle of radius 5.5 cm? answer in units of t.