From a bacterial standpoint, probably not. Still, refrozen ice cream and sherbet are less pleasant than the original product, mainly due to the larger ice crystals that would typically form in a home freezer than in an industrial or commercial ice cream maker. Also, melting the product releases the air that was beaten into the mixture during the production process, often 20% or more of the total volume. Refreezing it without beating more air back into it would just result in an icy solid.
Sleet
Sleet!
no
Wish
You get ice pellets, colloquially known as sleet in the U.S.
You get ice pellets, colloquially known as sleet in the US.
The salt temporarily melts the ice. The melted water flows over the string. The water refreezes on top of the string.
Sherbet will not react with water. It will generally dissolve in it. Sherbet refers to certain fizzy drinks, or to a sorbet-like dessert, and these food items will not react chemically with water.
The salt temporarily melts the snow, creating water. The water then refreezes, creating ice. Ice is much firmer, and faster than snow.
Because they form when the sun melts snow, but it's below freezing still so it refreezes. In the northern hemisphere, the south side receives more sunlight during the winter.
Sleet starts as snow, then falls through a layer of the atmosphere that is above freezing whereupon it melts into rain. Finally, it falls back into colder air and refreezes as ice pellets (sleet) before reaching the ground.
It's because sherbert ice cream is more of a water base (juice) which melts faster. Dairy base ice cream are usually made from egg yolk, cream, milk, and sugar. Yolks, cream, and milk have high fat content which makes them melt slower than water base ice cream which melts faster.