Schmidt hammer
A Schmidt hammer is a special tool that is used by grown-ups to test how hard a rock is.
When we hit the rock with the hammer, it makes a small dent on the surface. The Schmidt hammer then measures how much force is needed to make that dent.
We can use this information to figure out things like the strength of a building material. This is important because we don't want buildings to fall down or break easily!
So just like how we use different tools to measure different things like a ruler to measure length or a scale to measure weight, the Schmidt hammer helps grown-ups measure the hardness of rocks!
When we hit the rock with the hammer, it makes a small dent on the surface. The Schmidt hammer then measures how much force is needed to make that dent.
We can use this information to figure out things like the strength of a building material. This is important because we don't want buildings to fall down or break easily!
So just like how we use different tools to measure different things like a ruler to measure length or a scale to measure weight, the Schmidt hammer helps grown-ups measure the hardness of rocks!