Knowing that a 0.02-in. gap exists when the temperature is 758F,determine (a) the temperature at which the normal stress in thealuminum bar will be equal to 211 ksi, (b) the corresponding exactlength of the aluminum bar.Fig. P2.58 and P2.59
Recent Research Methods & Findings I. Inattentional Blindness A. Neisser & Becklen (1975) – showed simultaneous, superimposed videos. - People could follow one but not both of them this isn’t because they are inattentive, they are just paying attention to something specific this is called Inattentional Blindness because you’re perfectly alert and it’s right in front of you, but you don’t see it - unattended events often go unnoticed (auditory or visual) people might be very unaware of the limitations they have in attention inattentional blindness: unattended events/objects are not consciously noticed B. Change Blindness (see Matlin, p.76) example 1: when brief blanks are placed between alternating displays of an original and a changed scene, (uncued) ID of the change is very difficult even when a large change is repeatedly shown. [also found for changes that occur during a saccade] example 2: a gradual change in a scene is often missed unless you just happen to have your attention at the right place at the right times example 3: Simons & Levin (1994) – (1) “lost” person asks passerby for directions; (2) interrupted by 2 workers carrying a door; (3) lost person switches places with 2 worker as they pass Þ ~50% didn’t notice that person is different despite changes in clothes, voice, etc.! “visual perception of change in a scene occurs only when focused attention is given to the part being changed. … In the absence of focused attention, the contents of visual memory are simply overwritten (i.e., replaced) by subsequent stimuli and so cannot be used to make comparisons” (Rensink et al., 1997, PsychSci.). · People can be unaware of major changes that occur during a blink, an eye movement, or some distracting event. eyes move so fast that you are effectively blind for a moment while you move them · People are unaware that they have these limitations · blindness may be greatest at the center of gaze (these types of blindness might be worse at the center of your vision) · may be overconfident in tasks monitored by humans. conclusion: without focusing your attention on something, you won’t notice changes or even basic features II. Attentional Blink – when 2 targets are presented in rapid sequence (ISI
