Aprojectile travels above level ground. the initial vertical component of its velocity is 0.90 m/s and the initial horizontal component of its velocity is 0.60 m/s.
calculate the time the projectile remains in the air, and calculate the horizontal distance the projectile travels.

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

What happens when the number of protons in an atom changes

According to rutherford's nuclear theory, most of the volume of an atom is , so the volume of a hydrogen atom cannot be mostly due to the proton. according to rutherford's nuclear theory, the core of an atom (nucleus) contains most of of an atom and is , so the majority of the mass of a fluorine atom cannot be due to its nine electrons. according to rutherford's nuclear theory, the number of negatively charged particles outside the nucleus the number of positively charged particles within the nucleus, so a nitrogen atom has 7 protons and 7 electrons, while a phosphorous atom cannot have 15 protons and 150 electrons. word bank: dense, empty space, more than, mass, particles, the same as, less than, positively charged, negatively charged