During science class, while studying mixtures, you mix together iron filings and sand. Your teacher challenges you to separate t
he sand from the iron filings. How could you use the physical properties of matter to practically separate the two solids? A) Add water to the mixture and dissolve the sand.
B) Pick out one of the two solids by using color to guide you.
C) Pour the mixture through a paper filter to separate the two.
D) Use a magnet to pull out the iron filings as they are attracted to a magnet.
Eliminate
Answer : Use a magnet to pull out the iron filings as they are attracted to a magnet
Explanation : we use the magnet to separate the sand from the iron filing. Because the magnet has an attraction power.
We can say that we can use the magnet to attract the iron filings out of the mixture because iron is magnetic solid, but sand will not attract because sand is not magnetic solid.
So, we use a magnet to pull out the iron filings as they are attracted to a magnet.
and r=40 m, so we can re-arrange the previous equation to find the velocity of the car:
