Physics experiment 100 points will be awarded for those who answer well .

1. Slow down the fall speed (there is a large enough parachute and open it quickly before landing, if you use a line to tie it down slowly, you can also put it down, if you don't require the egg to fall without power...)

2. Cushion the impact of falling. Wrap the eggs in a sponge that is thick and fluffy enough.

3. Strengthen the anti-destruction ability of the egg shell (make the appearance of the egg glass cloth and resin into fiberglass, it will not break).

No matter what method is used, it is always inseparable from the above three routes.

It's just that the equipment and materials used are different.

You can make a small parachute for the eggs (the material is fine with an ordinary plastic bag, but the shape should be uniform).

You can also put eggs in cotton and sponges. In the soft package, as long as it is thick enough, there will be no problem.

You can also put the eggs in the balloon and let the balloon fill with water.

There is also a basin of water on the ground, a sponge (I don't know if it is possible).

According to the momentum theorem (ft=δmv), the velocity of the egg will always change from the same initial velocity to zero, so the key is to extend the time between the egg and the surrounding objects, that is, you can use soft objects to wrap the egg, such as sponge and cotton. Wrap the egg in these things and stuff it into a foam (like a TV, refrigerator). That way it won't break.

The A4 paper is cut into strips, and then fluffily laid on the ground, according to the impulse theorem: the longer the action time of i, the smaller the force f will be, because i does not change, only the time of action is increased, so such a method is feasible.

Make the chopsticks into a square shape, fix the port with gelatin or rubber bands, place the eggs in it, and then fix the eggs with the help of gelatin and rubber bands, the number of rubber bands depends on the situation, the principle is to use rubber bands as buffers.

Make the paper in the form of a parachute. Secure the egg at the bottom end.

Use a large water bag and put the eggs inside!

Cover the original one with a larger hydration bag! (Double Insurance).

Throw it down, the water has a buffering effect (momentum theorem), and it will be fine.

First wrap a thick napkin on the outside and wrap it slightly with glass glue... Fill the outside with toothpicks... Definitely won't break.

Experiments done in elementary school.

According to the momentum theorem: ft=δp=mδv, we know that δp is immutable, and in order to reduce the force, the action time should be increased, because it can be seen from the relation that f and t are inversely proportional. Therefore, to increase the action time, it is OK to spread a thick layer of sponge on the ground, because the egg has a downward impulse when it is lowered from a high place, and the thick sponge can play a buffering role, so that the egg will not rot.

Cut a large soda bottle, then put the right amount of rice in the larger part, bury the egg in the rice, then add the right amount of rice to the other half, and put the two halves together (tightly) so that it will not break.

It seems that the above friends are quite knowledgeable, and the formula is a lot. Know that it makes sense to ask these questions???

plastic bag, when parachute.

Protective device, with cotton, eraser, etc., wrap it and put it in the box, and the box should be filled.

Jump down with an egg in your pocket, being careful not to let the pocket hit the ground first.

Thread it through the box, like knitting a sweater, to form a pocket, put the egg in it, and stuff some cotton or sponge around it.

It's OK to make your house in a weightless environment.

What are you asking? Is there an expression of rx in the d-graph?

When the s1 is closed, the s1 is disconnected. The current i2 of rx+rl is measured when s,s1 is closed, and the current i1 of rx is measured.

Then, the voltage relation is.

rx+rl）*i2=u

rx*i1=u

Substitute the lower formula to the upper formula.

rx+rl）*i2=rx*i1

rx=rli2/（i1-i2）

Solution 1 is correct. Because your basis - the first law of thermodynamics is correct, and the analysis is also tenable.

Solution 2 is wrong. The first statement about "external expansion, the increase in the distance between molecules, and the increase in molecular potential energy" is true. But the second one is about"The temperature does not change, so the average kinetic energy of the molecules does not change"The statement is incorrect, because the title only tells us that it is under adiabatic conditions, that is, there is no heat exchange with the outside world, and it does not say that the temperature is constant.

In fact, the temperature of the gas is to be reduced, so that the total energy (internal energy) of the gas is reduced.

Concept of internal energy: The energy possessed by a large number of particles that are thermally moving inside an object is called thermal energy. These include the kinetic energy of the irregular motion of all the molecules inside the system and the potential energy of the interaction between the molecules.

Solution 1: Correctly use the first law of thermodynamics to analyze that there is no heat exchange, and the internal energy of external work is reduced.

Solution two mistakes: first: adiabatic is not the same temperature, but no heat absorption or heat release, no heat exchange. Second: when the distance between molecules increases, the potential energy of molecules does not necessarily increase, depending on whether the force between molecules is gravitational or repulsive. Therefore, the road is impassable.

As the intermolecular distance increases, the potential energy of the molecule increases, and it makes no sense that the distance has no certain relationship with the potential energy.

The temperature does not change, so the average kinetic energy of the molecule does not change Yes, but: The temperature will change.

Your solution is correct.

Solution 2 is incorrect, and the reason why it is incorrect is that as the molecular spacing increases, the molecular potential energy becomes smaller, not larger.

Solution 2, adiabatic does not mean constant temperature!

To put it simply, the gas does work externally, and the internal energy is reduced!

The potential energy of the molecule is larger, so the kinetic energy becomes smaller, and the change in kinetic energy is greater than the change in potential energy!

The solution is one pair, and the solution is wrong, because the temperature is not constant. Note: Adiabatic does not mean that the temperature does not change, but that there is no heat exchange with the outside world.

The change of temperature is not only related to heat transfer, but also related to the work done, and the energy will definitely be reduced if the work is done externally and there is no heat transfer, in fact, the temperature will be reduced. Don't confuse the concept of insulation.

Solution: Obtained from the diagram:

The total mass of the beaker and the liquid m1 = 50g + 2g = 52g, and the total mass of the remaining liquid of the beaker and the puff after pouring out the liquid m2 = 20g + 5g + 2g = 27g

The mass of the liquid poured into the graduated cylinder is m=52g-27g=25g As shown in the figure: the volume of the liquid in the graduated cylinder v=30cm3 is obtained according to the density formula:

liquid = m v = 25g 30cm3, so the answer is: 52; 27；25；30；

Equipment: Scale; Thin wire (very little elasticity); Pen.

Steps; 1. Align one end (the starting end) of the thin line with one end of the curve on the graph.

2. Let the thin lines be placed according to the curves in the figure and completely coincide. Mark with a pen the part where the thin line coincides with another end of the image.

3. Straighten the thin wire. Use a scale to measure the length from the start of the thin line to the mark. is the length of the curve in the diagram.

One is more powerful than the other, and they are all for others to answer.

BC inter-voltage application.

Equivalent circuit: AC

After the 2 resistors are connected in parallel, they are connected in series with B.

The galvanometer is the current of the A branch.

The total resistance is 2+2 2=3

The total current is 6 3 = 2A

So the A branch current is 1A

The current is expressed as 1a

Xiao Yu's favorite toy is a birthday gift from his uncle Three convex lenses of the same size and shape, made of glass, crystal, and plastic. Now Xiaoyu wants to **"whether the focal length of the convex lens of the same size and shape is related to the production". Please help him.

The whole process of designing this ** has completed the following work:

What equipment do you need this time? Please write it out.

Light screen, scale ruler. Convex lenses (made of glass, crystal, and plastic) ask you to write down the main steps.

In sunlight, different convex lenses are used to gather light, and when the spot is the smallest and brightest, the distance from the spot to the convex lens is measured with a scale to obtain the focal length of the convex lens of different materials.