ACTAR Visibility & Lighting Conditions 3

Question 1

Under FHWA minimum retroreflectivity guidelines, what is the minimum retroreflectivity level for white pavement markings?

Accepted Answer

100 mcd/m²/lux

Answer

50 mcd/m²/lux

Answer

200 mcd/m²/lux

Answer

300 mcd/m²/lux

Question 2

In a nighttime pedestrian collision reconstruction, 'recognition distance' differs from 'detection distance' in that:

Accepted Answer

Detection distance is where the object first becomes visible; recognition distance is where the driver can identify what the object is

Answer

Recognition distance is always numerically shorter than detection distance

Answer

Recognition distance applies only to moving objects such as cyclists

Answer

Detection distance requires the driver to be actively scanning for specific hazards

Question 3

Koschmieder's law is applied in accident reconstruction to:

Accepted Answer

Determine the visibility distance in foggy, smoky, or hazy atmospheric conditions

Answer

Calculate the energy absorbed during vehicle deformation in a frontal collision

Answer

Measure the coefficient of friction on wet pavement surfaces

Answer

Estimate vehicle speed from skidmark length and road grade

Question 4

A reconstructionist analyzing 'adverse lighting conditions' would consider which of the following as a significant factor in driver visual performance?

Accepted Answer

The dark adaptation state of the driver's eyes when transitioning from bright to dark environments

Answer

The color temperature of the vehicle's interior cabin lighting

Answer

The number of passengers present in the vehicle at the time of the collision

Answer

The manufacturer and model of windshield glass installed in the vehicle

Question 5

What effect does a wet road surface have on the retroreflectivity of pavement markings at night?

Accepted Answer

It decreases retroreflectivity because a water film prevents light from reaching retroreflective beads

Answer

It increases retroreflectivity by creating a specular mirror-like surface

Answer

It has no measurable effect on retroreflectivity values

Answer

It doubles the retroreflectivity reading under headlight illumination

Question 6

In nighttime accident reconstruction, an illuminance meter (light meter) is used to measure:

Accepted Answer

Ambient light levels at the accident scene in foot-candles or lux

Answer

Vehicle headlight output in lumens at the lamp source

Answer

The retroreflectivity of traffic signs and pavement markings

Answer

The color temperature of streetlights in Kelvin

Question 7

The 'nighttime viewing distance' for a stationary object in a roadway depends LEAST on which of the following?

Accepted Answer

The ambient air temperature at the accident scene

Answer

The headlight output of the approaching vehicle

Answer

The reflectivity and conspicuity of the object

Answer

The contrast between the object and its immediate background