If the horizontal component of a net force is 68 newtons and the angle made by the net force with the horizontal is 19.2°, what is the value of the net force?

The magnitude of the poynting vector of a planar electromagnetic wave has an average value of 0.939 w/m^2 . the wave is incident upon a rectangular area, 1.5 m by 2.0 m, at right angles. how much total electromagnetic energy falls on the area during 1.0 minute?

Derive the lens makers formula for convex les?

Which of the following can enter and exit a closed system? a. matter and energy b. neither energy nor matter c. matter but not energy d. enrgy but not matter