Mrs. Jenner's Class: March 2015

Monday, March 30, 2015

Chapter 9 Study Guide

Study Guide – Chapter 9 Motion

Key Terms are underlined and in bold. You need to know the definitions and examples/explanations for all key terms.

1. Describing Motion (Pages 338 – 341)

A. What is motion?

B. What is a reference point? Why is it important for the reference point to be a stable object?

C. If objects are moving together (like you when you drive home from school with your parents or a carpool) are they in motion relative to each other (relative motion)?

D. What are distance and displacement (a vector)? Be able to label on a map.

2. Speed and Velocity (pages 342 – 347)

A. What is speed? Know that speed is calculated with the formula

speed = distance/time. Be able to solve speed problems.

B. Average speed is the total distance covered divided by the total time covered.

C. Velocity is speed in a direction. The formula for calculating velocity is the same as for speed but you need to add a direction. Velocity is a Vector Quantity.

D. Be able to read graphs showing Time and Distance like the graphs on pages 346 and 347. You need to be able to describe the motion at each point.

E. On distance and time graphs, the steeper the slope, the faster the object is moving. The shallower the slope, the slower the object is moving.

3. Acceleration (pages 352- 355)

A. Acceleration is the rate at which velocity changes. If speed changes (faster or slower) OR direction changes, then an object has accelerated.

B. Be able to read a distance vs. time graph for acceleration like the one on page 355.

C. Be able to calculate the acceleration of an object given the velocities and total time like the acceleration lab in class. See page 353 for practice.

4. Energy (pages 358 – 363)

A. Energy is the ability to do work. Work is what is required to put an object in motion.

B. Potential Energy is stored energy. Be able to describe chemical, elastic and gravitational potential energy in real-life situations.

C. Gravitational potential energy depends on the height of an object and its weight. The more massive the object and the height of the object will determine the amount of potential energy.

D. Kinetic Energy is energy of motion. As an object falls is gains kinetic as it loses potential. Energy is transformed. Kinetic energy depends upon mass and speed but speed really affects the moving energy of an object.

E. The Law of Conservation of Energy says that energy cannot be created or destroyed, it only changes form. Be able to apply this law to the roller coasters we build in class, to how a pendulum moves, and also to explain why the pendulum CAN’T hit you in the face if you let it go from the tip of your nose.

F. Using the Law of Conservation of Energy, describe how energy changes form given a certain scenario like Sun -à Plant --à Person -àMarathon Run. Radiant Energy from the Sun transforms into Chemical Potential Energy (stored energy) which the person eats (Chemical Energy) to transform into Mechanical Energy and Thermal Energy.

Chapter 10 Study Guide

Study Guide: Chapter 10 Forces

1. Forces

A. A force is a push or a pull.

B. Net force is a combined force.

C. Unbalanced and Balanced forces

D. Force as a vector quantity

E. Force is measured in Newtons. A Newton is equal to about .22 pounds or 102 grams.

2. Friction Force

A. Friction is a force that acts opposite to a push or a pull.

B. When one surface interacts with another surface.

C. Four types of friction

D. Know what type of friction is being used in a situation and if you are trying to increase or decrease friction.

3. Elastic Force

A. Tension is a pulling elastic force

B. Compression is a pushing elastic force

4. Gravity

A. Gravity is a property of matter. The more matter and the closer you are to the matter, the greater the gravitational pull. The denser the object, the more gravitational pull.

B. Gravity is the force that pulls all objects toward Earth.

C. Free fall is when the only force accelerating an object is gravity. The acceleration due to gravity on Earth is 9.8 m/s2.

D. All objects fall at the same rate on Earth (as long as air friction is removed).

E. Monkey and the Hunter – Gravity is separate from forward motion so a shot object and a dropped object will fall at the same rate. Think running off a cliff vs. stepping off a cliff.