According to the kinetic theory of gases,when two molecules of gas collide with each other,then:

Electrons from excited chlorophyll molecule of photosystem $II$ are accepted first by

Which one of the following kinds of animals are triploblastic?

Which of the following orders is incorrect?

$A$ rectangular glass slab $ABCD,$ of refractive index $n_1,$ is immersed in water of refractive index $n_2$ $(n_1 > n_2)$. $A$ ray of light is incident at the surface $AB$ of the slab as shown. The maximum value of the angle of incidence $\alpha_{\max},$ such that the ray comes out only from the other surface $CD,$ is given by:

Blister copper is