Group B questions
The first question uses the acceleration and deceleration of the car as a model, draws a V-T diagram, and there is a brake trap hidden in the middle.
The second question is based on the actual braking problem, which needs to consider the actual reaction time of the person, and the problem becomes a multi-process problem. Develop students' analytical skills on practical problems.
The third question is an encounter chase problem, which is a typical model in kinematics, how to solve the encounter chase problem? The general idea is to analyze the motion characteristics of the two objects first, draw a schematic diagram of the process, and draw a V-T diagram to intuitively reflect the relationship between the motion of the objects. You can pay attention to the video that will be posted in a few days, "Using images to solve the problem of encounters and chasing"
The fourth question uses the traces of photographic photographs to calculate the relevant distance, which still requires the establishment of a motion picture.
The fifth question is the use of reverse thinking in a uniform acceleration motion with zero initial velocity.
The sixth question is the calculation of the time that the car can save through the ETC system, which is a scene that can be encountered in life, but it is easy to miss some time in the process of car movement in the actual calculation, or carefully analyze the movement and draw a motion V-T diagram, which can reduce errors.
In the reference solution, except for the question to draw a V-T diagram, there is no diagram in the others, and it is recommended that you can draw a diagram for each question, especially for the problems that meet and chase, as well as the problems of multiple processes or complex processes, all of which need to be drawn and analyzed.
