Summer Life Guidance 8th Grade Physics Exploration Answer 5

Physical Answer: p69

1， 80， （1）a,b,c a,d,f

2) fix a wooden board on the table, fix a nail at one end of the wooden board, fix a wooden board on the edge of the other end, the edge of the wooden board is very thin, and then fix one end of the string ready for test on the nail, and the other end through the wooden board, that is, a barrel, by increasing or decreasing the weight of the sand in the barrel to change the string to send in for the test.

3) The sand is not easy to be too heavy, and each string should be repeated several times.

p703 The reason why the small iron piece does not float on the surface of the water has nothing to do with its weight, but the 10,000-ton theory floats on the water because it occupies an area on the water and has a strong ability to bear it, while the small iron piece occupies a small area, and the sea water bears it less.

P714 (1) Temperature 2 In thermocouple circuits, the magnitude of the current decreases as the temperature between the borrowing points decreases.

3 Large measuring range P72 5

1. The effect of pressure is related to the weight of the object.

2. Weight weight.

3 The effect of pressure action is related to the cross-section and area occupied by the object pressed against the North Asian object.

Question 6. 1) 625,000 days (2) Approximately equal to 21 days.

Do you want me to write? I have the answer, but it's not cost-effective to score all 5 points.

8th grade physics summer vacation homework answers.

Junior high school physics is the foundation of physics learning, if you want to learn the subject of physics well, you must learn to do more questions and read more books from now on. For more information, please **** the new graduate examination network in time!

Chapter 1: 1Thermal expansion and cold contraction, 35 -42 2A: 11, B16, C: 9

3.The degree of heat and cold, the temperature is 4Ice-water fibrillation modified compound, boiling water at one standard atmospheric pressure, -273

5.Full contact with the thermometer glass bubble, the range of the thermometer (measuring range), perpendicular to the thermometer.

Kelvin, K, 316k

7.(1) Liquefaction, endothermic (2) Vaporization, endothermic (3) Condensation, exothermics.

8.(1) Vaporization (2) Liquefaction (3) Sublimation (4) Condensation.

9.Only on the surface, the slow vapor gauge phenomenon that can occur at any temperature increases the temperature of the liquid, accelerates the air flow on the surface of the liquid, and increases the surface area of the liquid. The occurrence site is different, the temperature conditions are different, and the speed of vaporization is different. Absorbs heat.

10.Crystalline, amorphous. To absorb heat, crystals have a fixed melting point, and amorphous hail destroyers do not have a fixed melting point.

11.(1) 230 (2) Solids heat, melt, temperature, heat absorption. The liquid rises, the liquid cools, and the liquid solidifies into crystals, releasing heat and cooling the solid. (3) 3, solid-liquid coexistence, coagulation, the former endothermic and the latter exothermic.

12.The temperature is low enough to increase the pressure of the liquid.

II, III, 1× 2.× 3.√ 4.× 5.× 6.× 7.√ 8.×

IV. 1Estimate the temperature of the object to be measured and look at the measuring range of the thermometer.

2.The glass bubble does not leave the object to be measured and does not touch objects other than the object to be measured.

3.Away from the object being measured, the line of sight is perpendicular to the thermometer.