the angle of incidence equals the angle of reflection

The first-attempt success catheterization was observed to be correlated to arterial depth ( p < 0.01, odds ratio 6.47). In this study, 119 patients were enrolled and 98 achieved first-attempt success. Categorized cases according to the cut-off values, the Kaplan-Meier analysis, and the log-rank test were used to determine the difference of first-attempt success with limited catheterized time between groups. The receiver operating characteristic (ROC) curve and the Youden index were used to explore the cut-off values of the arterial depth. Univariable and multivariable logistic regression analyses were performed to determine the association. Relevant variables were collected, including patients' demographics and catheterized information.

The cases undertaken by RAC within the DNTP technique between March 2019 and July 2020 were extracted from our institutional cohort database. This study also aimed to further explore the cut-off depth correlated to improved first-attempt success catheterization in less time. It is because of the law of reflection that an eye must sight at the image location in order to see the image of an object in a mirror.This study aimed to determine the associations between the first-attempt success and arterial depth in ultrasound-guided radial artery catheterization (RAC) with dynamic needle tip positioning (DNTP) technique. In fact, in each case, the image is not seen when sighting along the indicated line of sight. Neither of these cases would follow the law of reflection. In this case, for light from the object to reflect off the mirror and travel to the eye, the light would have to reflect in such a way that the angle of incidence is more than the angle of reflection. In Diagram B above, the eye is sighting along a line at a position below the actual image location. For light from the object to reflect off the mirror and travel to the eye, the light would have to reflect in such a way that the angle of incidence is less than the angle of reflection. This truth is depicted in the diagram below.įor example, in Diagram A above, the eye is sighting along a line at a position above the actual image location. Only when you sight at the image, does light from the object reflect off the mirror in accordance with the law of reflection and travel to your eye. If you were to sight along a line at a different location than the image location, it would be impossible for a ray of light to come from the object, reflect off the mirror according to the law of reflection, and subsequently travel to your eye. (The reason for this will be discussed later in Lesson 2). It just so happens that the light that travels along the line of sight to your eye follows the law of reflection. The diagram shows that the light reflects off the mirror in such a manner that the angle of incidence is equal to the angle of reflection. As you sight at the image, light travels to your eye along the path shown in the diagram below. To view an image of a pencil in a mirror, you must sight along a line at the image location. It is common to observe this law at work in a Physics lab such as the one described in the previous part of Lesson 1. (These two angles are labeled with the Greek letter 'theta' accompanied by a subscript read as 'theta-i' for angle of incidence and 'theta-r' for angle of reflection.) The law of reflection states that when a ray of light reflects off a surface, the angle of incidence is equal to the angle of reflection. The angle between the reflected ray and the normal is known as the angle of reflection. The angle between the incident ray and the normal is known as the angle of incidence. The normal line divides the angle between the incident ray and the reflected ray into two equal angles. This line is known as a normal line (labeled N in the diagram). At the point of incidence where the ray strikes the mirror, a line can be drawn perpendicular to the surface of the mirror. The ray of light that leaves the mirror is known as the reflected ray (labeled R in the diagram).

In the diagram, the ray of light approaching the mirror is known as the incident ray (labeled I in the diagram). The diagram below illustrates the law of reflection. If a ray of light could be observed approaching and reflecting off of a flat mirror, then the behavior of the light as it reflects would follow a predictable law known as the law of reflection. Light is known to behave in a very predictable manner.

The angle of incidence equals the angle of reflection