Тело массой 0, 3 при полном погружении вытесняет 350 см³ жидкости. будет ли оно плавать в воде? в керосине?

V=350 см³ = 0,00035 м³, m= 0,3 кг плотность этого тела p = m/v = 0,3/0,00035 = 857,14 кг/м³. плотность этого тела меньше плотности воды и в воде будет плавать, а в керосине утонет, т.к. его плотность больше плотности керосина.

дано: m=1 кг.

t2=27 град. цельсия.

q=?

l=25*10^3 дж/кг.решение: чтобы расплавить свинец , его нужно нагреть до температуры плавления, а после - плавить. то есть q будет равна сумме кол-ва теплоты, ушедших при его нагревании, и при плавлении.

где q1 - теплота при нагревании 1 кг. свинца до t=327 град. цельсия (до температуры плавления).

q2 - теплота при правлении. формула:

получаем:

где c - удельная теплоемкость свинца. c=0,13*10^3 дж/кг*с.

считаем:

q=1*(0,13*10^3*(327-27)+25*10^3)=1*(130*300+25000)=1*(39000+25000)=64000 дж=64 кдж.

ответ: q=64 кдж.

ответ:

если надо ввыучить то выбери

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