Science labs › Physics › Friction Drag Test
Pull a block with a newton meter. How hard do you have to pull on ice, wood or sandpaper?
Friction Drag Test lab · Last updated: 16 October 2026
You pull a block across different surfaces using a newton meter, the spring scale scientists use to measure force. On ice it slides easily; on sandpaper it takes a real tug. The lab turns a feeling into a number.
What you'll discover
- Friction is a force that pushes against sliding between two surfaces.
- Rough surfaces such as sandpaper grip harder than smooth ones such as ice.
- It takes more force to start a block sliding than to keep it moving.
The science in plain words
Friction is the force that opposes motion when two surfaces rub against each other. Even surfaces that feel smooth have tiny bumps and hollows. When they press together, these bumps catch on each other and form little temporary bonds, which resist sliding.
The rougher the surfaces, the more they catch, so the friction is greater. Ice is very slippery, partly because a thin watery layer on its surface helps things slide. Wood is in the middle. Sandpaper has sharp grains that dig in, so it needs the biggest pull.
A newton meter measures the pull in newtons, the unit of force. When you pull gently, friction pushes back just as hard and nothing moves. Pull harder and eventually the block starts to slide. Interestingly, once it is sliding, a slightly smaller pull keeps it going, because sliding friction is usually a little less than the friction holding a still object in place.
Heavier blocks press harder into the surface, so friction grows with the weight. Friction can be a nuisance, wearing out shoes and heating machine parts, but without it we could not walk, write or stop a bicycle.
Where it fits
- India, NCERT: Class 8 science, Chapter 5: Exploring Forces
- United States: Grades 6 to 8
- Next Generation Science Standards: MS-PS2-2
Common questions
What is friction in simple words?
Friction is a force that tries to stop two surfaces sliding over each other. It comes from tiny bumps on the surfaces catching on one another, and it is stronger on rough surfaces than on smooth ones.
Why is ice so slippery?
Ice has a very thin, watery layer on its surface that acts like a lubricant. The surfaces have little to grip, so friction is very low and things slide easily.
Is friction useful or harmful?
Both. Friction lets us walk, hold a pencil and brake a bicycle. It also wears out shoes and tyres and wastes energy as heat in machines, which is why we oil moving parts.
Related labs
- Slide and Light Gates: Let a toy sled slide down a slide. How fast does it pick up speed?
- Pulleys and a Newton Meter: Lift a brass weight with one wheel, then with more. How hard do you have to pull?
- Crashing Carts: Two carts crash on a track. Where does the push go?
See all physics labs or every Taz science lab.
Try it yourself
The Friction Drag Test lab is one of the interactive 3D science labs inside Taz. Change one thing, predict what will happen, then run it and watch. Labs open after you sign in.