Seek a professional English translation for the physical aspect

1. Does the velocity of an object change when the work of the various forces it experiences is 0?

2. In the following cases, does the medium do work? If you do work, is it positive or negative?

a. Chicks scratch the ground.

b. People read signal marks.

c. The crane lifts a bucket of concrete.

d. The gravitational force acting on the barrel.

3. A truck uses the movable ladder slope wood behind it (the truck comes with the slope or 2 planks to form a slope) to load furniture into the truck luggage; Is it correct to say that when the length of the slope increases and the horizontal angle of the ground decreases, there is a movement that decreases during the shipment? Explain why.

4. A pendulum swings back and forth, running well. In this process, does the rope that connects the bell hammer do work on the seed hammer? Does gravity do work on seed hammers? Explain why.

5. Two identical cars are coming in opposite directions, and the drivers of the two cars brake at the same time; The length of the brake marks of one car is twice that of the brake marks of the other car, and if the friction experienced by the two cars when braking is exactly the same, what conclusions can you draw about the motion of the two cars?

6. When a person who bets on football is playing football, when his toes are touching the ball, is he doing work at this time? When his toes are just off the ball, is he doing his work? When the ball flies out, is it doing power at this time?

7.A person lifts a cement block with a mass of kilograms vertically, vertically lifts it for a distance of meters, and then moves it horizontally and asks how much work this person has done in the process, and how much work has gravity done?

8.The vertical gravitational force on a mass of something on a planet is x 103 kg. Ask what is the work done by the various forces when this mass of things is lifted upwards by 30 meters from a state of rest with an acceleration of meters and square seconds.

It's so hard. You're not going to be an international student, are you?

The English language for physics isphysics。Physics is a natural science that studies the interrelationships between fundamental concepts such as matter, energy, space, and time, as well as their manifestations and laws in nature. In addition to physics, there are many other disciplines of English words.

The English word for chemistry is chemistry.

Chemistry is a natural science that studies the composition, structure, properties and changes of matter. It is one of the important branches of physics and biology.

The English word for biology is biology.

Biology is a natural science that studies the phenomena of life and the structure, function, development and evolution of life-friendly oaks. It is the foundation of disciplines such as medicine, agronomy, ecology, etc.

The English word for geology is geology.

Geology is a natural science that studies the material composition, structure, evolution, and changes in the Earth's surface. It is the foundation for the exploration of minerals, environmental protection, etc.

The English word for astronomy is astronomy.

Astronomy is a natural science that studies the celestial bodies in the universe, the origin, evolution, and structure of the universe. It is the foundation for the exploration of the universe, the development of space, the study of the earth's environment, and other fields.

The English word for psychology is psychology.

Psychology is a social science that studies the mind, emotions, behavior, and personality of human beings. It is the foundation of fields such as education, medicine, social work, etc.

The above are English words for several common subjects and their brief introductions. In study and work, mastering English words and related knowledge in these subjects is of great help to improve one's English and professional ability.

This Cong Heng excavated the basic limitations of the use of quartz tuning fork force detectors.

Scanning probe microscopy. The results show that at room temperature, the pressure while the atmosphere.

These pressure sensors have noisy floors PN AHZ display rms brown.

There is only the movement of points. When operating as a shear force sensor and reactive power. Two dissipations.

Samples are tested in the method. These forces are enough to reduce the amplitude.

The movement of the detector is almost zero on the surface of the body contact. It also shows.

Proportional-integral feedback controls yield, and conventional closed-loop reverse osmosis nuclei should be at least 40

times the rate of the ring-opening reaction.

The English above must be typed wrong.,Deal with it yourself.。

43。Throw three identical balls, all with the same initial velocity, juggling the clown to walk a tightrope. The first ball is thrown horizontally, the second is thrown at a level above a certain angle, and.

Third, throw at an angle below some air resistance, described.

The movement of the three balls and compare the speed of the balls as they reach the ground.

The velocity of the rubber ball in kilograms is determined at point A and the kinetic energy of J at point B is determined below.

In one. b Kinetic energy of the ball. The velocity of the ball is in B.

c。The total power done is from A to B

One. The center of gravity under the force.

b Work done. Lost due mechanical energy to friction.

c。The normal force of the work done.

and 46 blocks of inclination. A skier mass kg pulls up the slope by a cable driven by a motor. How much work is needed.

The skier pulls m, with a maximum slope of 35° (assumed frictionless), at a constant speed of meters and seconds.

47。Acrobats on skis start from a standstill on a frictionless track meters above the ground, and fly above the horizontal angle and at a height of meters above the track. Ignore air resistance.

What is the speed of the skier when leaving thetrack?

What is the maximum height reached.

48。Starting from a standstill, down a frictionless ramp from the ground to a kilogram of luggage slides meters. suitcase, then slide along the floor for an extra meter before stopping. Determine the following:

One. The speed of the suitcase is the slope at the bottom.

b。The floor of the trunk.

c coefficient of dynamic friction. due to friction.

49 changes in mechanical energy. The light horizontal spring spring has a spring constant of 105 Nm . A kilogram block compresses one end of the spring, compressing the spring meter.

After the block is released, the block moves meters to the right and only then rests. What is the coefficient of dynamic friction between the horizontal surface and the block? 25。

The spring force constant is Newton-meters. The potential energy stored in the spring is shown as follows:

Centimeters when the spring is stretched.

From the balance b. Centimeters when the spring is compressed.

From the balance c. When it is zero, the stretch of the spring.

43, A juggling clown stands on a taut rope and runs out 3 identical balls, all with the same initial velocity, the first ball is thrown horizontally, the second is slightly upward, and the third is slightly downward, regardless of air resistance, describes the trajectory of the 3 balls, and compares the speed at which they land.