These fundamentals checks are excellent for exam prep. You've been solving problems all year! With the exam approaching, you know how to finish a problem, as long as you know how to start. Well, on the AP exam, you can't ask a friend or a teacher how to start. These fundamentals checks will help remind you where to start.
I know it might not FEEL like doing a five-minute "quiz" each day isn't quite the studying that your friends, teachers, and parents expect. They talk about holing yourself up in a quiet cell doing practice problems for many hours.
They are wrong.
You're doing plenty of practice problems in your class. Outside of class, just do these fundamentals checks each day, and make sure you pay attention to the answers to whatever you get wrong. Have fun with them - challenge a friend or your classmates to see who gets the highest scores. Ask your teacher if they'll give a homework exemption for top scores. Bet a milkshake with some friends on your performance. Anything to make the process enjoyable.
Fundamentals Check #7
61. How do you find instantaneous angular velocity from an angular position vs. time graph?
63. An airplane has been cruising at a speed of 200 m/s for 10 s. What is the airplane's acceleration?
64. Write the equation for translational kinetic energy.
65. How do you determine the location of an object from a velocity-time graph?
66. An object on a vertical spring oscillates in simple harmonic motion. It's highest position is 30 cm above the ground; its lowest position is 20 cm above the ground. At what position above the ground is the object's speed largest?
67. Define "mechanical energy".
68. The equation for the weight of an object on earth's surface is GMm/r^2. How does the variable G in this equation change on the moon's surface, which is about 1/3 the diameter and 1/100 the mass of earth?
69. Write two expressions for angular impulse.
70. Under what conditions are the forces on an object balanced?
Solutions to Fundamentals Check 7:
ReplyDelete61. take the slope of a tangent line.
62. zero. (The angular momentum of a point object is mvr, where r is the distance of closest approach between the line of motion and the rotational axis. Here the line of motion goes directly through point P, so r = 0.)
63. zero. (Acceleration is the change in speed every second; this airplane doesn't change speed at all.)
64. (1/2)mv^2.
65. you can not. (You can determine *displacement* from the area under a velocity-time graph, but you cannot determine position.)
66. 25 cm. (At the equilibrium position of the spring, the potential energy of the spring-object-earth system is zero. Thus, all the energy of the system there is kinetic energy. The equilibrium position in simple harmonic motion is halfway between the two extreme positions.)
67. kinetic energy plus potential energy. (This includes all forms of kinetic energy, rotational and translational.)
68. it does not. (Big G is the universal gravitational constant, which is, well, *constant* throughout the universe.)
69. angular impulse is change in angular momentum; angular impulse is torque times time.
70. when acceleration is zero; that is, when an object is in equilibrium, moving in a straight line at constant speed.