Timed Test A block with a mass of 2 kg is pushed
20 cm at a constant speed up an incline
that makes a 40° angle with the floor.
How much work is done by gravity
on the block? Let D be the displacement
of the block

2.521 J
-3.003 J
-252.1 J
-2.521 J

Ann walks 80 meters on a straight line 33 ∘ north of east starting at point 1. draw ann's path. represent ann's walk with a vector of length 80 meters. draw the vector starting at point 1. the length given in the display is in meters.

Air is to be preheated by hot exhaust gases in a cross-flow heat exchanger before it enters the furnace. air enters the heat exchanger at 95 kpa and 20°c at a rate of 0.6 m^3/s. the combustion gases (cp = 1.10 kj/kg°c) enter at 160°c at a rate of 0.95 kg/s and leave at 95°c. determine the rate of heat transfer to the air and its outlet temperature.

Marvin records scientific data about lake superior. for which property has marvin forgotten to use an si unit of measurement? shore length high temperature low temperature annual precipitation