Xiao Ming once again used the density of 1.5 * 10 ^ 3kg / m ^ 3 rubber for shipbuilding competition, the volume of rubber he used was 20cm ^ 3, resulting in the maximum displacement volume of the boat is 200cm ^ 3. G = 10N / kg. P water = 1 * 10 ^ 3kg / m ^ 3? Write as many as you know, publicity

Xiao Ming once again used the density of 1.5 * 10 ^ 3kg / m ^ 3 rubber for shipbuilding competition, the volume of rubber he used was 20cm ^ 3, resulting in the maximum displacement volume of the boat is 200cm ^ 3. G = 10N / kg. P water = 1 * 10 ^ 3kg / m ^ 3? Write as many as you know, publicity

M rubber = ρ * V = 1.5 * 10 ^ 3 * 20 * 10 ^ - 6 = 0.03 (kg)
G rubber = m rubber * g = 0.03 * 10 = 0.3 (n)
F floating = f total = g drainage = P water VG = 1 * 10 ^ 3 * 200 * 10 ^ - 6 * 10 = 2 (n)
G load = f total - G rubber = 2-0.3 = 1.7 (n)
The steps must be right. There may be some mistakes in the calculation. If the answer is not right, please calculate according to the steps~

The problem of heat calculation for internal energy in Chapter 13 of physics is not only about heat, but more complicated

Let's give them first. Let's talk about them later
1. How much ℃ can the heat of 1.76 × 103J increase 500g lead from 20 ℃ (C lead = 0.13 × 103J / (kg ·℃))
2. Put a red iron nail with a temperature of 800 ℃ and a mass of 1.5g into a cup of 5 ℃ water to raise the water temperature by 15 ℃. How much heat does the nail release? What is the mass of water?
3. Put 420g of a metal block into boiling water for a long time, put it into a cup of 20 ℃, 46g of water, make the water temperature increase by 40 ℃, calculate the specific heat of the metal block
4. Pour 1kg of 80 ℃ hot water into 2kg of 20 ℃ cold water, regardless of heat loss. What is the mixing temperature of water?
5. 42% of the heat released from the complete combustion of 400g alcohol is absorbed by water. How much ℃ can 20kg water rise from 46 ℃ (1atm) (calorific value of alcohol q = 3.0 × 107j / kg)
6. When the mass ratio of a and B is 1:3, the heat absorption ratio is 2:3, and the temperature of a is twice that of B, what is the specific heat capacity ratio of a and B?
7. When the mass of cold water is m, the temperature increases from T1 to t after absorbing a certain amount of heat, and when the mass of hot water is 2m, the temperature also decreases to t after releasing the same amount of heat?
8. There are three pieces of metal with the same mass. The ratio of specific heat capacity is C A: C B: c c c c c c = 3:4:5. After they absorb the same heat, what is the ratio of increased temperature?
9. There are enough cold water at 20 ℃ and hot water at 70 ℃. In order to prepare 200 kg warm water at 50 ℃, how many kg cold water at 20 ℃ and hot water at 70 ℃ are needed (regardless of heat loss)
10. At present, there are 40 kg hot water at 70 ℃ and 40 kg cold water at 10 ℃. Regardless of heat loss, how many kg warm water at 38 ℃ can be prepared by using them?
11. After boiling 2kg metal block in boiling water for a period of time, take it out and quickly put it into 1.4kg water at 20 ℃. Finally, mix it at 30 ℃ to calculate the specific heat of the metal