A5-meter uniform plank of mass 100 kilograms rests on the top of a building with 2 meters extended over the edge as shown above. how far can a 50-kilogram person venture past the edge of the building on the plank before the plank just begins to tip?

Learning goal: to understand newton's 1st law. newton's principia states this first law of motion: an object subject to no net force maintains its state of motion, either at rest or at constant speed in a right line. this law may be restated as follows: if the sum of all forces acting on an object is zero, then the acceleration of that object is zero. mathematically this is just a special case of the 2nd law of motion, f⃗ =ma⃗ , when f⃗ =0. when studying newtonian mechanics, it is best to remember the 1st law in two ways: if the net force (i.e., sum of all forces) acting on an object is zero, the object will keep moving with constant velocity (which may be zero). if an object is moving with constant velocity, that is, with zero acceleration, then the net force acting on that object must be zero. complete the following sentences to see if you can apply these ideas. part a if a car is moving to the left with constant velocity, one can conclude that

Mr. polifka does a demonstration in science class. he holds an unlit match six inches above a candle flame. after a while, the match bursts into flame.

Increased ozone in the lower atmosphere near the ground results primarily from