when there are dented cans
<span>Q1. Diamond, Q2. Diamond, Q3. The amount of light bending depends on angle and wavelength the light enters the substance and how dense the substance is, Q4. If the second substance is more dense than the first, the light ray bends towards the ‘normal’, if it’s less dense it bends away, Q5. In the swimming pool, when you look at a person’s body underwater they appear disjointed.</span>
Answer:
The electron density of a polar bond accumulates towards one end of the bond, causing that end to carry a slight negative charge and the other end a slight positive charge. Likewise molecules in which there is an accumulation of electron density at one end of the molecule, giving that end a partial negative charge and the other a partial positive charge, are called polar molecules.
The electrons in the outermost shell of the covalent compounds are shared by nearby atoms. As there are no free electrons for conducting electricity, the covalent compounds are perfect insulators at absolute zero. As the temperature increases, some electrons move from valence band to conduction band. This gives rise to conductivity. But as the numbers of charge carriers are very low, covalent compounds are poor conductors. On the other hand metals are good conductors cause of their bonding. Metallic bonding consists of a sea of electrons rather than discreet bonds. The free electrons are able to move freely. Since electricity and heat need electrons to move, the bonding promotes conductivity.
It is because of the different neurotransmitters and their receptors.
Sympathetic stimulation of arterioles in skeletal muscle is mediated by epinephrine acting on its β-adrenergic receptors.
Sympathetic stimulation of vasoconstriction occurs as a result of activation of α-1 adrenergic receptors by norepinephrine released by post-ganglionic sympathetic neurons.
