Let’s go through each object one by one and match it with the correct simple machine.
---
1. Doorknob
A doorknob turns around a central rod (axle). When you turn the knob, the axle moves to open the latch. This is a
wheel and axle.
✔ Match: wheel and axle
---
2. Stapler
When you press down on the top of a stapler, it pivots on a point and pushes the staple into paper. That’s how a
lever works — it has a fulcrum, effort, and load.
✔ Match: lever
---
3. Nail
A nail has a sharp point that splits wood apart as it goes in. That’s what a
wedge does — it’s thick at one end and thin at the other to push things apart.
✔ Match: wedge
---
4. Bottle cap
You twist the cap to screw it on or off. The threads inside the cap wrap around like a spiral ramp — that’s a
screw.
✔ Match: screw
---
5. Shoelaces
Shoelaces go through eyelets and when you pull them, they change direction of force — kind of like a rope going over a wheel. That’s how a
pulley works (even though it’s not a real pulley, it acts like one).
✔ Match: pulley
---
6. Roof on a house
The roof slopes upward — it’s like a ramp. A sloped surface that helps move something up or down is an
inclined plane.
✔ Match: inclined plane
---
7. Shovel
When you dig, you push down on the handle and the blade lifts dirt. The shovel pivots near your hand — that’s a
lever.
✔ Match: lever
---
8. Fan
The blades spin around a center motor shaft. The blades are like wheels turning around an axle — so this is a
wheel and axle.
✔ Match: wheel and axle
---
9. Jar lid
Like the bottle cap, you twist the lid to tighten or loosen it. The ridges act like a spiral ramp — that’s a
screw.
✔ Match: screw
---
All matches are now checked and confirmed.
Final Answer:
- doorknob → wheel and axle
- stapler → lever
- nail → wedge
- bottle cap → screw
- shoelaces → pulley
- roof on a house → inclined plane
- shovel → lever
- fan → wheel and axle
- jar lid → screw
Parent Tip: Review the logic above to help your child master the concept of simple machines worksheet answer key.
