MCQ
The raincoats are made water proof by coating it with a material, which ............
- AAbsorb water
- BIncrease surface tension of water
- ✓Increase the angle of contact
- DDecreases the density of water
Raincoats are coated with material which increase the angle of contact, so water does not penetrates inside the layer.
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$(A)$For a given material of the capillary tube, $\mathrm{h}$ decreases with increase in $\mathrm{r}$.
$(B)$ For a given material of the capillary tube, $\mathrm{h}$ is independent of $\sigma$
$(C)$ If this experiment is performed in a lift going up with a constant acceleration, then $\mathrm{h}$ decreases
$(D)$ $\mathrm{h}$ is proportional to contact angel $\theta$
$\Delta\text{U}_1>\Delta\text{U}_2$
$\Delta\text{U}_1=\Delta\text{U}_2$
$\Delta\text{U}_1<\Delta\text{U}_2$
$\Delta\text{U}_1\neq\Delta\text{U}_2$