Simple Machines — Answer Key
Part A: Multiple Choice
Circle the best answer for each question.
1. Why does using a longer ramp require less force to move a heavy box?
A) The box becomes lighter on a longer ramp
B) The force is spread over a greater distance
C) Longer ramps have no friction
D) The box rolls faster on longer ramps
A longer ramp is gentler, so the same total work gets stretched out over a much longer push. Spreading the force over greater distance means each moment of pushing feels easier.
2. Which tool is an example of two levers working together?
A) A hammer
B) A pair of scissors
C) A screwdriver
D) A light bulb
Each scissor blade is a stiff bar that pivots on the central screw, so the two blades together act as two levers sharing one fulcrum. A hammer or screwdriver is just one tool, not a paired lever.
3. A child sits far from the fulcrum on a seesaw. What happens?
A) The seesaw breaks apart
B) The child has more lifting force on the other side
C) The seesaw cannot move at all
D) The child weighs less than before
On a lever, the farther a load sits from the fulcrum, the more turning force it creates. Sitting far out on a seesaw gives the child a stronger lifting effect on the opposite side.
4. Which simple machine would best help raise a bucket of water from a well?
A) Wedge
B) Inclined plane
C) Screw
D) Pulley
A pulley uses a rope over a wheel so you can pull down to lift up, which is perfect for raising a heavy bucket out of a deep well. Wedges split, ramps slope, and screws hold, none of which lift a bucket from below.
Part B: Fill in the Blank
Write the correct answer on each line.
1. A screwdriver turns a screw by acting as a wheel and axle.
A screwdriver has a wide handle (the wheel) attached to a thin shaft (the axle), and turning the wide handle spins the shaft with extra twisting force. The missing piece is the axle.
2. A wedge is a thick-to-thin shaped tool used to split or separate objects.
A tool with a thick back that tapers to a thin edge pushes objects apart as it is driven in, and that is the shape of a wedge.
3. The six simple machines are the lever, pulley, wheel and axle, inclined plane, wedge, and screw.
Counting the six classic simple machines gives lever, pulley, wheel and axle, inclined plane, wedge, and screw, so the missing one in the list is screw.
4. Construction workers use pulleys to lift heavy steel beams to the top of buildings.
Construction crews lift heavy steel beams high into the air by pulling down on ropes that run over wheels mounted at the top, which is the job of pulleys.
5. A bolt holds things together using spiral threads cut into its surface.
A bolt has spiral grooves cut along its surface that grip into matching grooves so things stay locked together. Those spiral grooves are called threads.