Emily planned an experiment for her science fair project. Why is it important for her to control variables during the experiment?
A. It will allow her to know which factor affected her results.
B. It will allow her to test several variables at a time.
C. It will allow her to communicate her results.
D. It will allow her to graph her results.
What is It will allow her to know which factor affected her results.
The forces acting on an object can either be balanced or unbalanced. If an unbalanced force is applied to an object, what might happen to the object?
a.
only the speed of the object might change
b.
only the direction of the object might change
c.
both the speed and direction of the object might change
d.
neither the speed or direction of the object might change
What is both the speed and direction of the object might change
The graph below shows the constant running speed of four different animals.
Which animals can have a constant speed that exceeds 40 miles per hour?
A. cheetah, quarter racehorse, greyhound and ostrich
B. cheetah, quarter racehorse and greyhound
C. cheetah, quarter racehorse and ostrich
D. cheetah, greyhound and ostrich
What is cheetah, quarter racehorse and ostrich
When two oppositely charged particles are brought near each other, they produce a force field. The illustration below shows the force around two charged particles.
Which force do the arrows represent?
a. an unbalanced force
b. a frictional force
c. an electrical force
d. a gravitational force
What is an electrical force
The drawing below shows three different positions of a skier as she descends a snow-packed hill.
Which statement about the skier is correct?
a. The skier’s kinetic energy is higher at point A than at point B.
b. The skier’s kinetic energy is lower at point C than at point B.
c. The skier’s potential energy is lower at point A than at point C.
d. The skier’s potential energy is higher at point B than at point C
What is The skier’s potential energy is higher at point B than at point C
Dalton is doing research on the internet to find facts for his science project. An on-line search returns the following sites. Which would be the best to use?
A. a website that does not provide the author's name
B. a blog of someone who studies astrology
C. an article from a scientific magazine
D. an online wiki
What is an article from a scientific magazine
At baseball practice, Takahiro and Alfredo both picked up the same bat and neither would let go until one of them had it for himself. Takahiro pulled the bat with a force of 15 newtons (N), while Alfredo pulled with a force of 20 newtons (N). Why did Alfredo end up with the bat?
a.
because the net force was 5 N in Alfredo’s direction.
b.
because the net force was 20 N in Alfredo’s direction.
c.
because the force was 5 N in Takahiro’s direction.
d.
because the net force was 15 N in Takahiro’s direction.
what is because the net force was 5 N in Alfredo’s direction
Plotting a graph of speed vs. time is a good way to see how an object’s motion changes, or stays constant, over time. Look closely at the Speed-Time graph below.
What can you conclude about the speed of the moving object plotted in this graph?
A. the speed of the object increases over time.
B. The speed of the object will increase after 4 hours.
C. The speed of the object is the same every hour.
D. The speed of the object changes between 1 and 3 hours.
What is The speed of the object is the same every hour
Leanna decided to rearrange her bedroom by moving her dresser to the opposite wall. She tried pushing it, but found that the dresser would not move. What force was Leanne NOT able to overcome?
a. electrical force
b. magnetic force
c. balanced force
d. frictional force
What is frictional force
Energy can be transformed from one type to another. In which of the following situations is kinetic energy transformed into potential energy?
a. when a boulder rolls down a mountain
b. when a water tank ruptures and water flows out
c. when a tree branch falls toward the ground
d. when a ball is thrown straight up into the air
What is when a ball is thrown straight up into the air
Hannah grows tomato plants in her garden. She wants to find out if the temperature of the water she provides to her tomato plants affects how tall the plants grow. What type of scientific investigation will best help Hannah answer her question?
A. mathematical model
B. systematic observations
C. experiment
D. physical model
What is experiment
An unbalanced force on an object can change its direction. Which of the following set of conditions would cause an object to move upward? N is the unit for force in newtons and the arrow indicates in which direction the force is being applied.
a.
20 N ↓ and 20 N ↑
b.
25 N ↓ and 20 N ↑
c.
30 N ↑ and 35 N ↓
d.
35N ↑ and 30 N ↓
What is 35N ↑ and 30 N ↓
Remember that speed = distance / time. If an object is moving at a constant speed of 3 meters/second, how far will this object travel in 4 seconds?
A. 6 meters
B. 9 meters
C. 12 meters
D. 15 meters
What is 12 meters
The illustration below shows Earth and the moon. The arrows represent the gravitational attraction between the two.
When is the gravitational attraction between Earth and the moon the strongest?
a. when the moon is full
b. when North America faces the moon
c. when Earth and the moon are the closest to one another
d. when Earth and the moon are the farthest apart from each other
What is when Earth and the moon are the closest to one another
The illustration below shows the path that a ball rolls, from left to right.
Which statement would correctly describe the energy of the ball as it travels along the path?
a.The ball has the most potential energy at point D.
b.The ball has the least potential energy at point A.
c.The ball has the most kinetic energy at point C.
d.The ball has the least kinetic energy at point D
What is The ball has the most kinetic energy at point C
Carol wants to determine how a fertilizer will affect the growth of marigolds. Which best explains why Carol would choose to investigate this topic using an experiment rather than systematic observations?
A. Her research question requires comparison, not notation and measurements.
B. Her research question should be answered using samples that are in identical circumstances.
C. Her research question requires changing one variable to see how it affects others.
D. Her research question involves studying a system that is too large or dangerous to study directly.
What is Her research question requires changing one variable to see how it affects others
A specific kind of force will result on an object when it is pushed from opposite sides. What must be true if the force on this object is unbalanced?
a.
The push must be equal in force on each side.
b.
The push must be greater on one side than on the other.
c.
Both pushes must apply a zero net force on the object.
d.
Both pushes must produce a net force so that the object remains in place.
What is The push must be greater on one side than on the other
Plotting a graph of distance vs. time is one way to determine an object’s speed. Review the graph below, which plots distance versus time for a moving object.
Why do the values on the graph form a straight line?
A. The speed is constant.
B. The distance remains unchanged.
C. The direction of motion stays the same.
D. The speed gradually increases over time
What is The speed is constant
Gravitational force between objects depends on mass and distance. Venus and Earth have about the same mass. However, the gravitational force between Venus and the sun is stronger than the gravitational force between Earth and the sun. What is the reason for this difference?
a. Earth is closer to the Sun.
b. Venus is closer to the Sun.
c. Venus and Earth are far apart.
d. Venus and Earth are close together
What is Venus is closer to the Sun
Energy can occur in many forms. Which of the following terms best describes kinetic energy?
a. motion
b. length
c. height
d. volume
what is motion
Ty and Crystal are working together to learn about surface tension. They each add pennies
to their own cup of water to see how many they can add before the cup overflows. Ty is able to add 15 pennies. Crystal is able to add 38. What should their next step be?
A. They should discuss differences in their methods.
B. They should each claim that their answer is right.
C. They should record their results and move on to a different investigation.
D. They should repeat the experiment using different pennies.
What is They should discuss differences in their methods
Which of the following must happen in order to determine the force acting on an object that is being lifted by a pulley?
a.
Gravitational force must be ignored.
b.
All the forces acting on the object must be measured.
c.
Only the forces pulling upward must be measured.
d.
Only the distance over which the object is lifted by the pulley must be measured.
What is All the forces acting on the object must be measured
Plotting a graph of speed vs. time is a good way to see how the motion of an object changes over time. Look closely at the graph below.
What can you conclude about the motion of the object?
a. The speed of the object is slowly increasing at a constant speed.
b. The motion of the object is decreasing at a constant speed.
c. The object is maintaining its direction of motion.
d. The object is returning to its original position
What is The motion of the object is decreasing at a constant speed
The width of the arrows in the illustration below represents the strength of the gravitational attraction between two objects
Using the law of universal gravitation, select the answer that best explains why the arrows are thicker in the top figure?
a. The gravitational force is slightly weaker in the top figure as compared to the bottom figure.
b. The masses of the objects in the top figure are different than the masses of the objects in the bottom figure.
c. The distance between the objects is shorter in the top figure as compared to the bottom figure.
d. The smaller object is in free fall
What is The distance between the objects is shorter in the top figure as compared to the bottom figure
What happens when an object is moved against gravity, such as rolling a toy car up a ramp?
a. Kinetic energy does not change.
b. Potential energy does not change.
c. Potential energy decreases as it is transformed into kinetic energy.
d. Kinetic energy is transformed into potential energy
What is Kinetic energy is transformed into potential energy