Heat. Control work №1    8-c

І-нұсқа.

1. How much heat will be allocated at complete combustion of dry birch firewood of volume 5 m³ ?

2. How much heats should be spent to heat up a pig-iron frying pan of mass 300 g from 20 up to 270 °C?

3. Changes of temperature of a metal detail of mass 100g from 20 up to 40°C needed 280 J energy. Define from what metal the detail is made.

ІІ-нұсқа.

1. At complete combustion coal with mass 10 kg is allocated 1,61*10⁵J of energy. To that the specific heat of combustion coal is equal? (1,61*10⁴J/kg)

2. On internal energy of boiled water, mass 200g, cooled down up to temperature 14°C how much will change?

3. At cooling up to 20°C internal energy of a copper body has decreased on 30.4 kJ. Up to what temperature the body is heated up, if its mass is equal 200g.