8th Grade Science U1 Test

What’s the formula for scientific notation?

m x 10^n

where ‘m’ is a real number between 1 and 10 (1 is less than or equal to m and 10 is greater than m).

‘n’ is an integer exponent.

What are the seven steps of the scientific method?

1. Observation

2. Question

3. Research

4. Hypothesis

5. Experiment

6. Analyze Data

7. Conclusion

What is slope (and its symbol)?

Slope is a measure of a line’s steepness.

Its symbol is m.

You solve for slope by doing rise/run.

What does a steep slope mean?

The slope dramatically changes (steeply rising or falling).

What does a shallow slope mean?

A shallow slope is basically the opposite of a steep slope, it gradually and gently rises or falls, and it has a low ratio of rise to run.

What does negative slope mean?

A negative slope means that as the x (independent variable) increases the y (dependent variable) decreases.

What’s the formula for density?

d = m/v

What is a “best fit line”?

A straight line drawn on a scatter plot to represent the fundamental linear relationship btwn two variables, minimizing the squared vertical distances from the actual data points to the line.

Why do we use a “best fit line” when graphing data?

To visualize the general trend of the scattered data points. This allows us to identify relationships.

Fill in the blank: The distance some points are from the “best fit line” indicate the amount of ____ in your measurement.

error

What does the rise in slope formula represent?

The y axis/vertical change.

What does the run in slope formula represent?

The x axis/horizontal change.

When setting up a graph what must be true about the numbering of the scale?

The ticks on the graph must be consistent and have equal intervals.

True or False: Every graph MUST have a title.

True

True or False: The formula for slope: Slope = rise/run is the same as d = m/v

For graphs conveying the relationship with density, mass and volume then true. Otherwise it’s false.

What are the “rates of change”?

How one measurement changes when the other measurement changes.

True or False: A line graph is used to show “rates of change” 

True.

When graphing, what is the variable that goes on the Y axis called?

The dependent/responding variable.

When graphing, what is the variable that goes on the X axis called?

The independent/manipulated variable.

What basic unit in the metric unit would you use to measure length?

cm

What basic unit in the metric system would you use to measure volume?

mL

What basic unit in the metric system would you use to measure?

grams (g)

How many grams are in a kg?

1000 grams.

How many liters are in a mL?

1/1000 liter

What is an independent variable?

What changes in an experiment.

What is a dependent variable?

What gets changed due to the independent variable.

What is the control group?

The group that stays the same in an experiment.

What is a valid measurement?

A measurement that is an estimated amount (in the general ballpark of the accurate measurement).

What is an accurate measurement?

The exact correct measurement.

What is the source of error?

Any factor or cause that limits the accuracy or precision of a measurement or experiment, leading to results that differ from the true value.

What is limitation?

Flaws or constraints or external factors that can affect the accuracy, reliability, and generalizability of the results.