Roy took 5 hours to complete a journey. For the first 2 hours, he travelled at an average speed of 65 km/h. For the rest of
the journey, he travelled at an average speed of 78 km/h. What
was the total distance of the journey?

Adouble-slit experiment is performed with light of wavelength 600 nm. the bright interference fringes are spaced 1.8 mm apart on the viewing screen.what will the fringe spacing be if the light is changed to a wavelength of 400 nm? ?

Which quantities are scalars? choose all that apply a.distance b.speed c. acceleration d.velocity

30 points - when can a theory be modified if a new type of technology allows for new observations that raise new questions? a. immediately, while the questions about the theory are being asked b. after new hypotheses related to the theory are tested in experiments c. only after the new observations disprove all parts of the theory d. while scientists begin to think about how the theory could improve