The atomic mass of a He atom is 4.  What is the mass of 3 x 10^23 atoms of such atoms in kg?

A ball initially has velocity in the positive direction.  It is struck by a bat, and reverses direction with the same speed.  Which is true of the CHANGE in the ball’s momentum over the interval it is struck by the bat? 

Which most closely describes refraction?

An hypothetical atom has atomic number 2 and atomic mass 2.  How many neutrons does it have?

Convert 1300 feet to miles (1 mile = 5280 feet).

2020 Hyundai Accent from second gear accelerates at a = 12 m/s2, speeding up while traveling along a straight line.  If the initial speed is 8 m/s, what is the speed after after 2.5 seconds?

Which of the following is NOT characteristic of ray optics?

A positive point charge and a negative point charge are separated by a small distance, and held stationary (so that the field resembles that of a dipole).  Which is true of the resulting electric field?

An industrial cylindrical barrel is partially full of oil.  It’s radius is 2 m, and it’s length is 20m.  It’s mass is 80kg.  What is it’s density?  

Consider a small black rubber ball, and a completely transparent glass marble, of the same size.  Which is true when they are subject to sunlight?