Mixing with a Common Drain. Two tanks, each holding 1 L of liquid, are connected by a pipe through which liquid flows from tank A into tank B at a rate of The liquid inside each tank is kept well stirred. Pure water flows into tank A at a rate of 3 L/min. Solution flows out of tank A at ? L/min and out of tank B at 3 - ? L/min. If, initially, tank B contains no salt (only water) and tank A contains 0.1 kg of salt, determine the mass of salt in each tank at time t ? 0. How does the mass of salt in tank A depend on the choice of ? What is the maximum mass of salt in tank B? (See Figure 9.3.)

NEWTON’S LAWS OF MOTION 1. Objects at rest stay at rest and objects in motion stay in motion unless an outside force acts a. force changes motion b. rest feels the same as uniform motion i. you only feel changes in motion c. there’s no such thing as centrifugal force 2. Acceleration (change in motion) is directly proportional to applied force and inversely proportional to inertia (mass) a. a = f/m i. usually written as F = ma b. weight is not the same as mass c. mass is the property of an object (its inertia) d. weight = force of gravitation ON an object 3. Every action has an equal and opposite reaction a. forces always come in pairs i.