Prologue

• Briefly, what is science?

• Throughout the ages, what has been the general reaction to new ideas about established "truths"?

• List the steps of the scientific method.

• A change of mind of often a sign of weakness (flip-flopping). How is this different from the attitude that prevails in science?

• What is the test for whether or not a hypothesis is scientific?

• How are science and religion similar?

• How are the concerns science and religion different?

• Must people choose between science and religion? Explain.

• Psychological comfort is a benefit of having solid answers to religious questions. What benefit accompanies adopting a position of not knowing answers?

• What is the importance of people learning nature's rules?

• Did Aristotle believe that forces are necessary to keep objects moving, or did he believe that, once moving, they would simply continue to move?

• What idea of Aristotle did Galileo discredit with his experiments on balls rolling on an incline?

• Where is your weight greater: on the Moon or on Earth? How about your mass? Explain.

• What is the net force on a box that is being pushed to the right with 50N of force while, at the same time, being pushed to the left with 20N of force? Include both magnitude and direction.

• One bowling ball sits at rest, and another bowling ball rolls down a lane at constant speed. Which ball is in equilibrium? Defend your answer.

• If you push to the right on a heavy piece of furniture and it slides, what is the direction of friction on the furniture?

• Distinguish between speed and velocity.

• Distinguish between velocity and acceleration.

• What is the acceleration of an object that moves at constant velocity? What is the net force on the object in this case?

• What is the acceleration of an object in free fall at Earth's surface?

• State the law of inertia.

• When a bird lets go of a branch and drops to the ground below, why doesn't the moving Earth sweep away from the dropping bird?

• What kind of path would the planets follow if suddenly their attraction to the Sun no longer existed?

• State Newton's 2nd Law.

• Why doesn't a heavy object accelerate more than a light object when they are both freely falling?

• What is the net force that acts on a 10N falling object when it encounters 4 N of air resistance? 10N of air resistance?

• What is the acceleration of a falling object that has reached its terminal velocity? Explain.

• State Newton's 3rd Law.

• Consider hitting a baseball with a bat. If we call the force of the bat against the ball the action force, what is the reaction force?

• If the force that acts on a cannonball and force that acts on the recoiling cannon from which it is fired are equal in magnitude, why do the cannonball and the cannon have very different accelerations?

• Which has greater momentum: an automobile at rest or a moving skateboard? Why?

• Why is it advantageous in karate to apply a force for a short time? Explain using impulse.

• What does it mean to say that a quantity is "conserved"?

• Railroad car A rolls at a certain speed and makes a perfectly elastic collision with car B of the same mass. After the collision, car A is observed to be at rest. How does the speed of car B compare with the initial speed of car A?

• Which requires more work: lifting a 50kg sack a vertical distance of 2m, or lifting a 25kg sack a vertical distance of 4m. Explain your answer.

• A car is raised a certain distance in a service station lift and therefore has potential energy relative to the floor. If it were raised twice as high, how much potential energy would it have compared with what it had in the first place?

• If a moving car speeds up until it is going 3X as fast as it was, how much kinetic energy does it have compared with its initial kinetic energy?

• An apple hanging from a limb has potential energy because of its height. If the apple falls, what becomes of this energy just before the apple hits the ground? When it hits the ground?

• What is the efficiency of a machine that converts all the input energy into useful output energy? Is that situation possible in the physical world?

• What is the ultimate source of the energy supplied by fossil fuels, dams, and windmills? What is the ultimate source of the energy supplied by geothermal energy?