Who can provide the total review material for Senior 1 Physics 20

I have hunger from Shanghai Middle School.

There is no pressure in the first year of high school, and reading books is the first.

Ask your teacher and read more books.

Explanation 5Newton's first law: Any object that is not subject to any external force always maintains a state of uniform linear motion or a state of rest until an external force acting on it forces it to change this state.

Hence ab wrong . Inertia is an intrinsic property of the object and is therefore false.

7.When throwing, the resistance is the largest, the weight is subjected to the weight and the direction of the resistance is downward, and the resultant force is gravity plus the resistance b at the highest point, and the velocity is zero, and only the gravity is applied.

c When the resistance is upward, the resultant force is gravity minus resistance, the minimum acceleration is a=f m, the greater the resultant force, the greater the acceleration, so choose a

A: 1First of all, to do circular motion, there must be a centripetal force, then the plane can do a circular motion around the earth, that is to say, the attraction of the earth is the centripetal force of the plane to do a circular motion, c answer is correct, ab is wrong, because the object is in a weightless state, so d is correct.

2.Because it is necessary to overcome the gravitational pull of the earth, it must have a minimum launch velocity, and this velocity is the first velocity of the universe, because when the satellite moves in a circle around the earth, the velocity is less than the first velocity, because the distance increases, and the satellite is subjected to less force.

The velocity that a spacecraft must have when moving in a circle along the earth's surface is also called orbital velocity. First, there are two aliases for cosmic velocity: the minimum launch speed of the spacecraft and the maximum operating speed of the spacecraft.

In some cases, it is said that when a spacecraft is moving at the first cosmic velocity, it means that the spacecraft is moving along the Earth's surface. According to the theory of mechanics, it is possible to calculate v1 7 9 km seconds.

Second Cosmic Velocity When an object (spacecraft) flies at a speed of kilometers and seconds, it can get rid of the shackles of the earth's gravity, fly away from the earth and enter an orbit around the sun, and no longer orbit the earth. This minimum velocity out of the Earth's gravitational pull is the second cosmic velocity.

Third Cosmic Speed When a spacecraft taking off from the earth reaches a speed of 1,000 kilometers and a second, it can break free from the shackles of the sun's gravitational pull and enter the wider universe from the solar system. The lowest speed at which the Earth can take off from the solar system is the third cosmic velocity.

(1) When launching an artificial satellite, the acceleration process of the satellite has not yet entered the orbit, due to the vertical upward acceleration (or the acceleration has a component in the vertical direction. The object inside the satellite is overweight, a situation similar to that of an object in an elevator.

2) After the satellite enters the orbit, during normal operation, the acceleration of the satellite is equal to the gravitational acceleration at the beginning of the orbit, and the objects in the satellite are in a state of complete weightlessness.

I think the first question should be a CD

The first cosmic velocity is the maximum orbital velocity and the minimum launch velocity of the satellite. The second cosmic velocity around the earth is the minimum velocity of an object to break free from the gravitational pull of the earth, and the third cosmic velocity around the sun is the minimum velocity of an object to break free from the gravitational pull of the sun

Question 2 b The first cosmic velocity is the maximum velocity of the artificial earth satellite flying around the earth Therefore b false c the second cosmic velocity is the minimum launch velocity of the satellite from the earth's gravity and escaping into the solar system d the third cosmic velocity is the minimum launch velocity of the artificial earth satellite and leaving the solar system 1 a the attraction of the earth and other planets is the centripetal force and provides it with centripetal acceleration a false b balances with the centripetal force b false c feels c is also right.