How much does a pebble weight in grams
How much does a pebble weight in grams
The Correct Answer and Explanation is:
A typical pebble weighs between 10 to 100 grams, depending on its size, shape, and the type of rock it is made from. For example, a small pebble about the size of a grape (around 2–3 cm in diameter) usually weighs around 20 to 50 grams. Larger pebbles can weigh more, while very small ones may weigh less than 10 grams.
Explanation
The weight of a pebble depends primarily on its volume and the density of the material it is made of. Pebbles are small, rounded stones usually formed by natural weathering and erosion processes. Over time, water, wind, or ice breaks down larger rocks into smaller fragments, which are then smoothed out and rounded to form pebbles.
1. Size and Volume
Pebbles are typically classified as being between 4 mm and 64 mm in diameter. This is based on the Udden-Wentworth scale, which is used in geology to classify sediment particles. Since volume increases with the cube of the diameter, even small differences in size can significantly affect a pebble’s weight.
2. Density of Rock Types
Different rock types have different densities:
- Granite: ~2.7 g/cm³
- Basalt: ~3.0 g/cm³
- Sandstone: ~2.3 g/cm³
- Limestone: ~2.5 g/cm³
Assuming an average density of 2.6 g/cm³ and a roughly spherical shape with a 3 cm diameter (volume ≈ 14.1 cm³), the pebble would weigh about 36.7 grams (mass = volume × density).
3. Shape and Moisture
Irregular shapes and internal porosity can slightly reduce the actual weight. Wet pebbles can weigh more due to moisture absorption or surface water.
Conclusion
So, a typical pebble commonly weighs between 10 to 100 grams, with 30–50 grams being average for those about the size of a golf ball. To get an exact weight, one would need to measure the specific pebble using a scale
.