eQuizShow

Physical Science

Forces and Motion

Question: What is Newton's First Law of Motion?
Answer: Law of Inertia. The velocity of an object does not change unless an unbalanced net force acts on it.

Question: What force would you need to apply to a 10 kg ball to make it accelerate 2 m/s/s?
Answer: F=ma = 10 kg x 2m/s/s = 20N

Question: What does the slope of a straight line on a distance vs. time graph tell you about the motion of an object?
Answer: The slope is speed. A straight line would tell you the speed is constant.

Question: Describe how the gravitational force between two objects would change if the masses of the objects increased but the distance betweem them stayed the same.
Answer: As mass increases, the gravitational force increases.

Question: Name the action reaction pair of forces that allows a rocket to speed up/slow down/change direction in space.
Answer: The action force is the rocket pushes fuel in one direction. The reaction force is the fuel pushes the rocket in the opposite direction.

Energy

Question: Name the 6 forms of energy.
Answer: Mechanical, Chemical, Thermal, Electrical, Radiant, and Nuclear

Question: Calculate the GPE of a 5 kg object resting on a shelf that is 6 m above the ground.
Answer: GPE = mgh = 5kg x 10m/s/s x 6m = 300 J

Question: Calculate the kinetic energy of a 10 kg bowling ball moving down the alley at a velocity of 50 m/s.
Answer: KE = 1/2mv2 = .5(10kg)(50m/s)(50m/s) = 12500J

Question: Energy Transformation: Trace the path of energy for a lightbulb, starting at the electric socket.
Answer: Electrical --> Thermal --> Radiant

Question: What is the kinetic energy of a 3 kg ball right before it hits the ground if it is released from rest at a height of 4m?
Answer: GPE is mgh = 3kg x 10m/s/s x 4m = 120J

Law of conservation of Energy - energy is not created or destroyed

KE right before it hits the ground (GPE = 0 J) must be 120J

Electricity

Question: What is Ohm's Law?
Answer: V=I x R

V= voltage
I= current
R= resistance

Question: A circuit which has multiple pathways for current to flow is known as _____________________ circuit.
Answer: Parallel

Question: The image below shows a ___________________ circuit.


Answer: series

Question: What will happen to the current if voltage increases?
Answer: The current will increase

I = V/R

Question: If the voltage across the battery in both diagrams is 20 V. What is the voltage across each lamp in the top image? The bottom image?


Answer: Top image --> 10V across each lamp

Bottom image --> 20V across each lamp

Waves

Question: What are the 2 types of mechanical waves?
Answer: Transverse and compression/longitudinal

Question: What is the difference between mechanical waves and electromagnetic waves?
Answer: Mechanical requires a medium and electromagnetic waves do not.
Mechanical the speed varies with the medium whereas electromagnetic all travel at the same speed (300,000,000m/s)

Question: Name the wave interaction that is the "bending of waves around an obstacle".
Answer: Diffraction

Question: When the crest of one wave meets with the trough of another, what type of interference is that?
Answer: Destructive interference

Question: The pitch of a train's whistle drops as it approaches and passes you at the railroad crossing. Why does this happen and what is the name of this phenomenon?
Answer: As the train is coming towards you, it is moving into its waves which the causes the frequency to increase (higher pitch). As the train passes and moves away, it is stretching out the waves so the frequency decreases and the pitch is lower. This is known as the Doppler Effect.

Scientific Inquiry

Question: Based on research, you make a prediction that watering your plant with diet coke will make it grow faster than watering it with just water. What is the scientific name for this prediction?
Answer: Hypothesis

Question: What is an explanation of things or events that is based on knowledge gained from many observations and investigations?
Answer: A theory

Question: Calculate the Density of an object that has a mass of 10 grams and a volume of 5 cubic centimeters.
Answer: D = m/v = 10g/5cm^3 = 2 g/cm^3

Question: Jeremy predicts that sleep deprivation will help students perform better on their midterms. He divides his class into 2 equal groups. One group gets a full night of sleep and the other group pulls and all nighter. Both groups study the same. After the exam, the tests are graded. What is the independent variable? Dependent variable?
Answer: Independent Variable - amount of sleep Dependent Variable - Score on test

Question: What is an observation? Give an example.

What is an inference? Give an example.
Answer: Observation is information gathered through the senses it is fact--> example the grass is green
Inference is a logical conclusion based on observations --> the grass is green because it is fertilized