Magnets and Engineering Design

Grade 3 Science Worksheet

Circle the answer.

1. 1.

   A magnet pulls a steel can but not an aluminum can. Which design could sort cans for recycling?

   • a magnet that lifts the steel cans out
   • a sieve with holes as big as cans
   • a magnet that lifts the aluminum cans out
   • a net that catches cans by color
2. 2.

   Two magnets pull together hard when they are 1 cm apart. What happens when they are 5 cm apart?

   • they pull with the same force
   • they pull together more strongly
   • they pull together more weakly
   • they push apart
3. 3.

   A student wants a magnet latch to keep a box lid shut. Which magnet ends should meet when the lid closes?

   • two north poles
   • a north pole and a south pole
   • any two ends, since it does not matter
   • two south poles
4. 4.

   A paper clip hangs from a string. A magnet comes close without touching it, and the clip moves toward the magnet. What does this show?

   • paper clips are magnets
   • the string pulls the clip
   • magnets must touch to pull
   • magnets can pull without touching
5. 5.

   A balloon rubbed on a sweater picks up tiny bits of paper. A second balloon rubbed the same way is held near the first. What happens?

   • nothing happens
   • the paper bits fall off
   • the two balloons push apart
   • the two balloons pull together
6. 6.

   Which design uses magnets to solve a problem?

   • a sponge mop for spills
   • a plastic rake for leaves
   • a paper bag for trash
   • a magnetic sweeper that picks up dropped nails
7. 7.

   A student counts how many paper clips a magnet holds through cardboard cards. Use the graph. What pattern does it show?

   • 5 cards held the most clips
   • more cards between means fewer clips
   • the cards make no difference
   • more cards means more clips
8. 8.

   A magnet pulls a steel screw, but not a brass key. What can you conclude?

   • brass is a kind of steel
   • all metals are pulled by magnets
   • not all metals are pulled by magnets
   • magnets pull only screws
9. 9.

   Two ring magnets on a pencil float one above the other. Why?

   • the pencil is a magnet
   • their facing poles are the same, so they push apart
   • air holds the top magnet up
   • their facing poles are opposite, so they pull
10. 10.

    Which object is attracted to a magnet?

    • a steel screw
    • a copper wire
    • a glass marble
    • a gold ring