The angle of incidence for a light wave is 42°. What is the angle of reflection?

Atrain departs from its station at a constant acceleration of 5 m/s. what is the speed of the train at the end of 20s?

What is the force that opposes motion and works against the downward pull? a) friction b) gravity c) weight d) acceleration

Panel bc in fig. p2.76 is semi-circular, with the 3 meter radius and horizontal straight edge through point b. compute (a) the hydrostatic force of the water on the panel, (b) its center of pressure, and (c) the moment of this force about point b. assume atmospheric pressure on the dry side of the panel