Potential Barrier

(redirected from potential barriers)

potential barrier

[pə′ten·chəl ′bar·ē·ər]
The potential in a region in a field of force where the force exerted on a particle is such as to oppose the passage of the particle through the region. Also known as barrier; potential hill.

Potential Barrier


the spatially bounded region of high potential energy of a particle in a field of force on both sides of which the potential energy decreases quite abruptly. The potential barrier corresponds to the repulsive force.

A potential barrier of simple form is illustrated in Figure 1 for the case of linear motion of a particle along the x-axis. When x = x0, the potential energy V(x) assumes a maximum value V0, which is called the height of the potential barrier. A potential barrier divides space into two regions (I and II), in which the potential energy of the particle is less than that in the region (III) within the potential barrier.

In classical mechanics, the passage of a particle through a potential barrier is possible only when the particle’s total energy ℰ—kinetic energy plus potential energy—exceeds the height of the barrier, that is, when ℰ≥ V0. If, however, the energy of the particle is insufficient to surmount the barrier, ℰ< V0, then the particle, moving from left to right, stops upon reaching the barrier at xi and moves in the opposite direction. The potential barrier is a sort of opaque wall or barrier, hence its name, for particles with energy less than its height.

Figure 1

In quantum mechanics, in contrast to classical mechanics, the passage of particles with energy less than V0 through the potential barrier is possible. This phenomenon is called the tunnel effect. It also happens that particles with energy greater than V0 are sometimes reflected from the barrier. These peculiarities of the behavior of particles in quantum physics are directly related to the wave-corpuscle nature of subatomic particles. The tunnel effect is significant only in systems having microscopic dimensions and masses. The narrower the potential barrier and the smaller the difference between the height of the barrier and the total energy of the particle, the greater the probability of tunneling.

References in periodicals archive ?
"Increased knowledge of variables linked to relapse among former smokers may help identify areas where clinical and public health efforts can be directed to reduce threats to relapse among individual former smokers, as well as potential barriers to sustained abstinence, and associated health and societal benefits at a population level in the United States," the authors write.
In an effort to understand the level of preparedness of key UK suppliers, we are communicating proactively with them and working together to resolve any potential barriers to supply."
The agency recognizes a number of potential barriers to the prospects for Iraq, including world market conditions, foreign investment, political stability and a steady supply of water needed for real oil production.
Tenders are invited for assessment of potential barriers and routes for decentralised energy schemes in rural and urban fringe areas in the uk
"This program recognizes the potential barriers to breastfeeding for lower-income patients who are less likely to initiate and sustain it," said Jane Karol, Practice Manager of the NorthShore Community Health Center.
to discuss how potential barriers created by sight loss can be overcome in order to allow those who are vision-impaired or blind to participate in disciplines such as photography, painting, mosaicing and woodwork.
"However, a big part of the Start programme is about removing any potential barriers to one of Britain's most successful Olympic sports.
The questionnaire was developed using existing validated questions covering these domains: willingness and confidence, knowledge of the association between obesity/sugar consumption and oral health, self-evaluated abilities on screening and giving advice regarding sugar consumption and obesity, and potential barriers to providing advice.
The important thing is to talk about the potential barriers and how you'd handle them.
Consider the potential barriers that could get in the way of achieving your goals and plan out how you will overcome these obstacles in advance.
This report aims to create visibility of the potential barriers that female-led businesses and entrepreneurs appear to have long faced in accessing finance; highlighting that opportunities for women entrepreneurs do not seem to have been equal.

Full browser ?