A window washer drops a brush from a scaf- fold on a tall office building.
What is the speed of the falling brush after
2.74 s? (Neglect drag forces.) The accelera-
tion due to gravity is 9.8 m/s
How far has it fallen in that time?

Aboat that travels with constant speed of 6.10 m/s in still water is to go directly across a river. the current in the river flows at 1.95 m/s. (a) at what angle must the boat be steered?

How have the competing explanations' experiments on atoms affected the development of the atomic model?

An engineer designs a roller coaster so that a car travels horizontally for 152 ft, then climbs 137 ft at an angle of 34.0° above the horizontal. it then moves 137 ft at an angle of 48.0° below the horizontal. if we take the initial horizontal motion of the car to be along the +x-axis, what is the car's displacement? (give the magnitude of your answer, in ft, to at least four significant figures and give the direction of your answer in degrees counterclockwise from the +x-axis.)