Experimental Design

Which experiment listed below will best determine how friction affects the speed of a rolling object?

• Roll 3 objects of various sizes across the floor.
• Roll 3 objects of equal size from various heights across the floor.
• Roll 3 objects of equal size across 3 different types of surfaces.
• Roll 3 objects of equal size from equal heights across the floor.

Tags

NGSS.MS-PS2-2

When designing an experiment, why is it important to test only one variable?

• Testing one variable explains what  caused the change once data has been gathered.
• Testing one variable collects inaccurate data and repeats the investigation more than necessary.
• Testing one variable decreases the reliability of the investigation.
• It is not necessary to test only one variable.

Tags

NGSS.MS-PS2-2

NGSS.MS-PS3-4

Looking at the picture, what two tools would be needed to measure the effect of friction on the ball?

• Hand lens and balance
• Balance and spring scale
• Measuring tape and stop watch
• Spring scale and hand lens

When conducting an experiment, in order to get reliable results, it is important to:

• Disregard results that do not match your hypothesis
• Test many different variables at the same time
• Test all forces at the same time
• Repeat the investigation several times

A student drops a ball from shoulder height. The ball bounces 5 times before coming to a stop. What force causes the ball to fall to the ground?

• Friction
• Magnetism
• Position
• Gravity

Tags

NGSS.MS-PS2-2

NGSS.MS-PS2-4

Which experiment listed below will best determine how friction affects the speed of a rolling object?

• Roll 3 objects of various sizes across the floor.
• Roll 3 objects of equal size from various heights across the floor.
• Roll 3 objects of equal size across 3 different types of surfaces.
• Roll 3 objects of equal size from equal heights across the floor.

Tags

NGSS.MS-PS2-2

A student uses a spring scale to pull a 50-gram block horizontally across a wood desk. Then the student pulls the block the same distance across surfaces of carpet, sandpaper, and glass. Which question is this investigation most likely designed to answer?

• How do blocks of different sizes react to force?

• How do different surfaces affect the amount of force needed to move a block?

• How do blocks affect spring scales?

• How does the mass of a block change when it is pulled across a desk?

Tags

NGSS.MS-PS2-2

Some students attach a balloon to a straw and then they tape the straw to the top of a toy car. The students inflate the balloon and release the car. The car travels 40 centimeters across the floor. What should the students do to determine whether the force of the air from a balloon is enough to push the car 40 centimeters across the the same floor in repeated trials?

• Test the car several times using an identical balloon filled with different amounts of air.

• Test the car several times using different-sized balloons filled with the same amount of air.

• Test the car several times using an identical balloon filled with the same amount of air.

• Test the car several times using different-sized balloons with different amounts of air.

Tags

NGSS.3-5-ETS1-1

NGSS.3-PS2-1

NGSS.3-PS2-2

A student observes that the craters on the moon are different sizes. The student designs an experiment to study the formation of craters. The materials for the experiment are marbles and a pan of flour. The student makes a hypothesis that the size of the craters made on the surface of the flour will depend on the height from which the marble is dropped. Some of the steps in the student's experiment are described. Which of these is most likely Step 3 in the student's experiment?

• Drop the same marble from different heights into the pan of flour

• Drop marbles of different masses from the same height into the pan of flour

• Drop marbles of different sizes from different heights into the pan of flour

• Drop a single marble one at a time into the pan of flour

A student designs an experiment to test the force of spring using a spring launcher and four spheres with the same diameter but with different masses. What other piece of equipment would be most useful for this experiment?

• A graduated cylinder to measure a volume of each sphere before the sphere is launched.

• A beaker to collect the spheres after they have been launched

• A stopwatch to measure how long it takes to load each sphere on the spring

• A meter stick to measure the height each sphere reaches after the sphere is launched

Tags

NGSS.MS-PS2-1

NGSS.MS-PS2-2