Science Test Thursday!

We have a science test over chapter 3 on Thursday. It covers forces, motion, speed, velocity, and forces of water.

Be sure to complete chapter 3 packet and chapter 3 review, both due Thursday.

There is no math homework.

The chapter notes are as follows:

Chapter 3 Notes

Sec. 3-1 Describing, Measuring, and Graphing Motion
I. Changing Position- Recognizing Motion
A. Motion-
1. definition- object is in motion when its distance from another object is changing
2. reference point- a place or object used for comparison to determine if something is in motion; an object is in motion if it changes position relative to a reference point
B. Describing Distance: SI- Basic SI unit of length is the meter (m).
C. Calculating Speed
1. speed- the distance an object travels in one unit of time (speed= distance/time)
2. Constant speed- an object whose speed does not change
3. Average speed- total distance / total time traveled
D. Describing Velocity
1. def.- speed in a given direction
2. the speed and direction of an object’s motion
E. Graphing Motion

Sec 3-2 Force & Acceleration
II. Forces and Motion
A. Force- a push or a pull on an object
1. Force can cause an object to start or stop moving or change the way that an object is moving
2. Net force- overall force acting on an object
3. unbalanced force- a force that changes an object’s motion
a. unbalanced force results when multiple forces are exerted on an object in the same direction
b. unbalanced force may also result when two forces act in different direction on the object
4. Balanced force- equal forces acting on one object in opposite directions
a. Forces cancel each other out
b. Balanced forces do not change object’s motion
B. Types of Forces
1. Contact forces- force exerted by two objects in contact with each other that push away
2. Friction- the force that one substance exerts on another when the two rub against each other
3. Gravitational Force- the force that pulls you and everything near Earth’s surface towards Earth’s center
4. Magnetic Force- attraction of a magnet to metal
5. Electrical Force- attraction between charged parts of atoms (static electricity)
C. Acceleration
1. def.- the rate at which velocity changes
2. Increasing speed- any time an unbalanced force causes the speed of an object to increase causing acceleration
3. Decreasing speed- motion in which speed decreases or slows down
4. Changing direction
5. Calculating Acceleration
a. change in velocity during each unit of time
b. Acceleration = (final velocity – initial velocity)/ time
6. Graphing acceleration
a. linear relationship- the graphed line rises the same amount on each axis
b. nonlinear relationship- the graphed line varies the amount of each axis

Sec. 3-3
III. Water in Motion
A. Rivers Shape the Land
1. Erosion- the process by which fragments of soil and rock are broken off from the ground surface and carried away
2. Deposition- process by which soil and rock are dropped in a new location
3. Force of moving water shapes many features of Earth’s surface
4. Sediment- particles of rock andsoil picked up andmoved by erosion and deposition
5. River Flow
a. Faster water moves, more energy
b. Speed affected by:
i. steepness of slope
ii. volume of water in the river
iii. slope of the channel
B. Profile of a River
1. Headwaters- small streams that come together at the source of the river
2. Downriver
3. Flood Plain- broad, flat valley through which the river flows
4. Meanders- looping curves in the river formed by erosion
5. Obow lake- crescent-shaped, cutoff body of water remaining from a river breaking through the ends of a meander
6. Mouth- the point where a river flows into another body of water
7. Delta- deposits at the river’s mouth
C. Rivers and Floods
1. Flood- occurs when the volume of water in a river increases so much that the river overflows its channel
2. Flooding river can erode and deposit huge amounts of soil, sand, and gravel
3. Floods can uproot trees and pluck boulders from the ground
4. Levees- sediment deposits that build up over time into long ridges that parallel the river


BEST OF LUCK!!!