# Harper mid-term

## 70 terms · this is just general but all sections

### Hypothesis

Must be a statement, not a question
Links tow variables
Example: Women who exercise have greater bone density than those who are sedentary.
Tall girls are stronger than short girls.

### Independent variable

cause
Height of plants (whether tall or short)
it is the part of the experiment that is the same for both sides

### Dependent variable

Effect
It is the part in the experiment that is different.
Length of the ears of corn

### control

(set up to give us something to compare the experimental group to) the "normal" group
The control group and the experimental group should be alike in every way except for the independent variable.
In addition to being in the same level of science course, the students should also be alike in other ways: basic intelligence, adequate nutrition, identical testing situations, etc. These factors are called constant factors or constants.

### experimental group

The group that is doing the experiment
The control group and the experimental group should be alike in every way except for the independent variable.

### conclusion

It sums up the experiment and all that happened
It must reflect the hypothesis.

### constant factors

That remain the same in both groups in an experiment- so the group will be as similar as possible except for the independent variable

### experiment

A test of a hypothesis
Controlled experiment contains:
An experimental group
A control group (set up to give us something to compare the experimental group to) the
"normal" group
Suppose you want to know whether studying with music helps students do better on tests.
If you just have students study with music and then look at their grades, it is meaningless
unless you have grades when they studied in silence to compare them to.

### Control Conclusion Hypothesis Independent variable Dependent variable Experimental group Constant factor

Be able to Identify the parts of a controlled experiment from an articles or description of a study

### ...

be able to design an controlled experiment to solve a given problem

### volume

The metric units for this are the liter and the milliliter.
You use a graduated cylinder to find it

### mass

the amount of matter in an object.
Metric units for mass are the gram and kilogram.
Electronic balance helps to find this

### Density

the measure of how far apart objects are.
Metric units for distance include millimeters (mm), centimeters (cm), meters (m), and kilometer(km)

### temperature

Metric unit of measure for temperature is the degree Celsius.
All temperature measurements made in the lab will be in Celsius degrees

### Distance

The metric units of this are meter and the centimeter
Meter stick is used to measure
Metric units for distance include millimeters (mm), centimeters (cm), meters (m), and kilometers (km).

### gram

Metric units measures mass of an object

### liter

Metric unit to measure volume

### meter

Metric unit to measure distance

### Graduated cylinder Flask Beaker Pie peck Evaporating tray balance funnel look at lab equipment flash cards with pictures also

identify some lab equipment

### Kilo hecto Deca M,L,G deci centi milli

Convert units within the metric system.

### Speed

Rate of motion, change, or activity
Speed: distance
Time
· Speed is the same as rate (that you studied in math)
· Constant speed: stays the same

### velocity

When speed or direction change......
speed changes.
OR
Direction changes
The velocity of an object moving in a circle changes because... an object traveling in a circle at a constant rate of speed changes its velocity because its direction changes.
So the planets constantly change velocity even though their speed does not change.

### motion

Rate in which something moves
A change in the position of an object with a respect for time

### Acceleration

Rate of change in velocity: speeding up, slowing down, or changing in direction.
Happens when speed changes

### Deceleration

Slowing down
Answers are negative

### Momentum

mass of an object times velocity

### Gravity

the force of attraction between all objects in the universe
A pull toward the center of the earth

### Unbalanced force

not equal and opposite forces

### Frame of reference

Whenever you describe something that is moving, you are comparing it with something that is assumed to be stationary, or not moving. The background or the object that is used to compare motion to is called this. It is wherever you are when you observe something moving.
Where you are observing something happen

push or pull

### weight

a measure of the force of gravity on the mass of an object

### Newton's 1st law

Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it.

### Newton's 2nd law

Acceleration is produced when a force acts on a mass. The greater the mass (of the object being accelerated) the greater the amount of force needed (to accelerate the object)

### newton's 3rd law

For every action there is an equal and opposite re-action

### Battery

one or more electrochemical cells that convert stored chemical energy into electrical energy

### Fuse

short circuits can be avoided using devices that melt if too hot

### Photo resistor

light sensitive- the more light that shines on it the more it resists

### Inertia

the resistance of any physical object to a change in its state of motion or rest.
the tendency of any object to stay at rest or in motion until an outside force acts on it

### Circuit

path containing easily moveable charges. when the light bulb lights up, charges (electrons) are flowing through the wire and light bulb.

### conductor

materials with easily moveable charges. when the light bulb lights up, charges (electrons) are flowing through the wire and light bulb

### Insulator

a substance that resists the flow of electrical current

### electric current

a flow of electric charge or the rate of flow of electric charge

### Resistor

resists- reduces the flow of electricity

### static electricity

the buildup of electric charge on the surface of objects

### Lightning

a discharge of atmospheric electricity, accompanied by a vivid flash of light, commonly from one cloud to another, sometimes from a cloud to earth. the sound produced by the electricity in passing rapidly through the atmosphere constitutes thunder

### Chemical energy

stored in bonds. released or absorbed when bonds are broken

### Gravity

attraction between all objects in the universe, the force of attraction between all forces in the universe

### Potential energy

Stored energy or the ability to do work because of position

### electrical

waves of electrons that move from one place to another

### Heat (thermal)

kinetic energy of particles of a substance, when energy increases the particles speed up. when energy decreases the particles slow down

### Light

Electromagnetic waves that are visible to the eye

### sound

Vibration of particles of matter that travel from one place to another

Energy of motion

### electromagnetic

waves with an electrical and magnetic component

### solar

Radiant light and heat from the sun

### Geothermal

Energy from moving water

### Gases

Particles father apart- moving freely and quickly

### atoms

smallest particles of an element

atoms

molecules

### neutrons

In the nucleus of an atom and is neutral

### protons

Nucleus of an atom and positive

### subatomic

particles which are smaller than an atom

part of an atom

### electron

In the electron cloud and negative

### Solid

vibrating particles that are close together; definite shape and volume

### Liquid

particles close flowing over one another; definite volume takes shape of container

### Plasma

High energy
Can destroy most matter

### mass

The amount of mater in an object
the mass of an object is constant.
It does not change when the object moves from one place to another as weight does.

### Weight

Pull of gravity on an object
Weight does change when: you go from the earth to a place where there is a different pull of gravity.