Students learned that objects can exert forces on other objects without touching.
Which three investigations will provide evidence to support what they
have learned?
b
C

measuring how close a soda can must be before it rolls toward a balloon that has been rubbed on someone's hair
counting the number of staples that are directly attached to a strong magnet
dropping a rubber ball from a distance of 1.5 meters above the classroom floor
placing a magnet against a jar containing a mixture of iron filings and sand
measuring how far a toy car travels across the floor before coming to a stop
d
e

How does the presence of oxygen affect the chemical pathways used to extract energy from glucose?

State one important difference between a physical change and a chemical change?

Electromagnets coils of wire paper clips picked up 10 3 15 6 20 9 25 12 ms. owens' class was studying magnets. ms. owens showed her students how to make an electromagnet using a nail, a d-cell battery, and plastic coated wire. the students wrapped the wire around the nail and then attached the ends to the battery. when they were finished, they tested their magnets by investigating how many paperclips their magnets could pick up. they also tested whether they could increase the strength of their electromagnets by using more coils of wire. they recorded the class average of their results in the data table seen here. ms. owens asked her students to graph their data in a line graph. how should the students label the x-axis on their line graph? a) size of battery b) number of paper clips c) number of coils of wire d) strength of electromagnet