NCERT Solutions Curiosity Chapter 7 .4.1 Seepage of water beneath the Earth — In-text Questions

Book page 1007 Updated on2026-09-05

Q1.

Do your findings match with your predictions?

Answer

Yes — for most students the findings match the prediction exactly: water seeps fastest through gravel, slower through sand and slowest through clay.

If they do not match: that is useful information, not a failure. Check whether the clay was packed too loosely, whether the hole in one cap was bigger than the others, or whether the gravel was full of fine dust. In science, a prediction that fails sends you back to look for the reason — which is how the activity teaches you to keep every other condition the same.

Tip: write down your prediction before pouring the water. Comparing an honest prediction with the observation is the whole point of the Prediction and Observation columns in Table 7.5.

Q2.

You may have observed that water seeps fastest through gravel, slower through sand, and slowest through clay. Why is it so?

Answer

Because of the size of the spaces between the particles.

Gravel — large particles, wide, open, connected spaces → water seeps fastest
Sand — smaller particles, narrower spaces → water seeps slower
Clay — very fine, closely packed particles, tiny spaces → water seeps slowest

Why it happens: water can only move through the gaps between particles, not through the particles themselves. The spaces between gravel particles are wider when compared to those in sand and clay, so water can seep through the gravel more easily. Water can infiltrate more readily if the spaces between soil and rock particles are wider, open and interconnected (Fig. 7.11). In clay the gaps are so fine and so poorly connected that the water is almost stopped.

Did you know? The same rule works underground. Layers of sand and gravel below the surface make good aquifers, because they can both take in water and hold a lot of it in their pore spaces.

Was this helpful? Report an error