Science Midterm review Mrs. DeVone

Scientific Method Recognize the problem Form a hypothesis How? Observe & Infer What is observation? Information you can get using your senses What is Inferring? A conclusion based on your observations (example: a tall tree ~ must be old) Form a hypothesis What is a hypothesis? A prediction you make about the outcome of an experiment based on your problem. Created in the “if, then” format (If I count the rings inside the tree, then I will know how old the tree is.)

Scientific Method Test your hypothesis Analyze your data How? Plan and implement an experiment (Step by step instructions) Analyze your data How? Data will be presented in an orderly fashion usually in some type of chart (the tree had 25 rings) Draw conclusions How? Look at the data and make some conclusions (The tree is 25 years old) Communicate your findings How ? Let others know what you found out with your experiment through a report or chart or poster.

Vocabulary Hypothesis – a testable prediction about a possible solution to a problem. Inference – conclusion drawn from an observation Observation – something you figure out based on your senses.

Vocabulary Independent variable – the one factor in an experiment that changes Example: 3 different types of soil to see which helps a plant grow best Dependent variable – factor that will be measured in an experiment Example: How tall the plants grew.

Constant – factors in an experiment that stay the same. Vocabulary Constant – factors in an experiment that stay the same. Example: same type of plant, same pot, same amount of water Control – is a standard used for comparison Example: one plant in potting soil to compare the other plants to

Experiment Read experiment – What is the experiment about? (Hypothesis) Independent variable – what did they do different to each group? Dependent variable – How were they measuring the experiment? Constants – what was the same for both groups? Control group – Which group did not have testing done to it? Conclusion - did the amount of sleep affect the score?

Lab Safety Name safety rules

Metric System Measurements Tool/ Equipment Unit Length ruler, measuring tape, meter stick meter Mass Triple Beam Balance Grams Volume (Liquid) Graduated Cylinder Liter

density . Find the density of an item when m=30g and v=6mL D=M/V D= 30g/6mL D=5 g/mL Oil is able to float on water because it is…. Less dense than water

density What is the density of water? A marble will sink in water because it is…. 1g/ml More dense than water

density If a substance is more dense than water it sinks; if it is less dense than water it floats.

Vocabulary Velocity- speed and direction of a moving body Acceleration-when an object speeds up, slows down, or changes direction

Vocabulary Inertia- an objects tendency to continue the motion it currently has. Inertia is affected by mass. The more mass, the more inertia.  Force (including unit)- push or pull that has a size and direction (Newtons)

Vocabulary Balanced forces- forces that are equal but opposite in direction Unbalanced forces-unequal forces that do not cancel each other when acting on an object and cause a change in the objects motion.

Vocabulary Friction-force between two surfaces in contact that resist the sliding of the surfaces past each other.

Laws of motion 1st Law of Motion- an object will remain at rest or move in a straight line with constant speed unless acted upon by an outside force. 2nd Law of Motion- an object acted upon by an outside force will accelerate in the direction of the force.

Laws of motion 3rd Law of Motion- forces always act in equal but opposite pairs.

Laws of motion A change in position is … The total distance traveled divided by the total amount of time is… You are riding a bicycle down a hill. When you reach a busy intersection, you apply your breaks. This is an example of…. motion Average speed acceleration

Laws of motion A ___________ has the greatest inertia. The inertia of an object increases when the _________ increases. If the action force of an object is 15N to the left, the reaction force must be… Bowling ball mass 15N to the right

Laws of motion A person in a head on collision, who is not wearing a seatbelt, continues to move forward at the original speed of the car because… When you push off the side of the swimming pool, the force of our foot on the wall is created _____ the force of the wall on your foot inertia At the same time

Laws of motion What is the force that keeps you from sliding off a sled when it starts moving? Static friction

Identify the following lab equipment:

How to read metrics: metric ruler, graduated cylinder, beaker 6.6mL 14.3 cm