The current shape of the North American continent (the present-day territory of the United States of America and Canada) was formed 25,000 years ago. At that time the great northern icecap flowed over the North American continent. This ice flow determined the size and drainage of the Great Lakes. They changed the direction of the Missouri River and carved the channel of the Hudson River. They created the northern part of the Central Agricultural Basin, which is one of the richest farming areas in the world.
On the Atlantic shore of the United States, much of the northern coast is rocky. But the middle and southern Atlantic coasts rise gently from the sea. The Appalachians, which run almost parallel to the east coast, are old mountains with many coal rich valleys between them To the west of the Appalachians, lie plateaus built up over the centuries from bits of stone that were washed down from the mountains and then cut into small hills by streams. Beyond is the great Central Lowland which resembles the plains of Eastern Europe.
Предположим, весь лед растает. На это потребуется 680 кДж. Горячая вода может остыть только до 0, отдав при этом 378 кДж. С учетом потерь - 341 кДж Значит весь лед растопить не удастся. Для нагревания на 5 градусов 2 кг льда нужно 2100*2*5=21 кДж (уд. теплоемкость льда 2100 Дж/(кг*К) ) Вся остальная теплота (341-21=320 кДж) уйдет на плавление части льда. Расплавить мы сумеем 320/340=0.94 кг льда. В результате получим равновесную систему лед+вода при температуре 0 градусов, в которой будет 1,94 кг воды и 1,06 кг льда
The current shape of the North American continent (the present-day territory of the United States of America and Canada) was formed 25,000 years ago. At that time the great northern icecap flowed over the North American continent. This ice flow determined the size and drainage of the Great Lakes. They changed the direction of the Missouri River and carved the channel of the Hudson River. They created the northern part of the Central Agricultural Basin, which is one of the richest farming areas in the world.
On the Atlantic shore of the United States, much of the northern coast is rocky. But the middle and southern Atlantic coasts rise gently from the sea. The Appalachians, which run almost parallel to the east coast, are old mountains with many coal rich valleys between them To the west of the Appalachians, lie plateaus built up over the centuries from bits of stone that were washed down from the mountains and then cut into small hills by streams. Beyond is the great Central Lowland which resembles the plains of Eastern Europe.
На это потребуется 680 кДж.
Горячая вода может остыть только до 0, отдав при этом 378 кДж. С учетом потерь - 341 кДж
Значит весь лед растопить не удастся.
Для нагревания на 5 градусов 2 кг льда нужно 2100*2*5=21 кДж (уд. теплоемкость льда 2100 Дж/(кг*К) )
Вся остальная теплота (341-21=320 кДж) уйдет на плавление части льда.
Расплавить мы сумеем 320/340=0.94 кг льда.
В результате получим равновесную систему лед+вода при температуре 0 градусов, в которой будет 1,94 кг воды и 1,06 кг льда