1.
If intensity of sound is increased 100times (100 people are talking all at once), then the intensity level of sound increases by
Correct Answer
D. 20 dB
Explanation
When the intensity of sound is increased 100 times, the intensity level of sound increases by 20 dB. This is because the intensity level is measured on a logarithmic scale, where every 10-fold increase in intensity corresponds to a 10 dB increase in intensity level. Since the intensity is increased 100 times, it corresponds to a 10-fold increase twice, resulting in a total increase of 20 dB.
2.
Central visual field:
Correct Answer
D. Corresponds to the angle of 0? - 30? with the optical axis of an eye
Explanation
The central visual field refers to the area directly in front of the eye, where vision is sharpest. It corresponds to the angle of 0° - 30° with the optical axis of the eye. This means that the central visual field extends 30° to either side of the optical axis. This range is considered to be the most important for tasks requiring high visual acuity and detail, such as reading or focusing on a specific object.
3.
Visual sensitivity is defined as
Correct Answer
A. Sensitivity (dB) = 10 x log (maximum intensity / set intensity
Explanation
The correct answer is Sensitivity (dB) = 10 x log (maximum intensity / set intensity. This formula is used to calculate visual sensitivity in decibels (dB) based on the ratio of the maximum intensity to the set intensity. The logarithm function is used to compress the range of values and make it easier to compare different levels of sensitivity. The factor of 10 is used to convert the logarithm base from natural logarithm (ln) to base 10 logarithm, which is more commonly used in practical applications.
4.
Relative audiogram:
Correct Answer
B. Expresses hearing loss in decibels in comparison with the values of normal threshold of hearing
Explanation
The relative audiogram expresses hearing loss in decibels in comparison with the values of normal threshold of hearing. This means that it provides a measure of how much a person's hearing ability deviates from the normal range. The decibel scale is commonly used to quantify the intensity of sounds, and in this case, it is used to represent the degree of hearing loss. By comparing the individual's hearing thresholds to the normal threshold, the relative audiogram can provide valuable information about the extent of their hearing impairment.
5.
Perimetry is a method
Correct Answer
B. For examining visual field of eyes
Explanation
Perimetry is a method used to examine the visual field of the eyes. It involves measuring the extent and sensitivity of a person's peripheral vision. This test helps to identify any areas of vision loss or abnormalities in the field of vision. By mapping out the visual field, healthcare professionals can diagnose and monitor conditions such as glaucoma, retinal detachment, and optic nerve damage.
6.
Watt per square meter is the unit for
Correct Answer
A. Intensity of sound
Explanation
The unit "watt per square meter" is used to measure the intensity of sound. Intensity refers to the amount of energy that is transmitted through a given area in a specific direction. It is a measure of the power of the sound wave per unit area. Therefore, the correct answer is "intensity of sound."
7.
Minimal angle of resolution (MAR) and visual acuity (V) are approx. in the relation:
Correct Answer
B. V = log MAR
Explanation
The given relation V = log MAR implies that visual acuity (V) is equal to the logarithm of minimal angle of resolution (MAR). This means that as the MAR decreases (i.e., the ability to distinguish fine details improves), the visual acuity increases. The logarithm function is used here to represent the relationship between these two variables.
8.
Audiometer is an electroacoustic device which is constructed for:
Correct Answer
B. Examination of function of organ of hearing
Explanation
An audiometer is an electroacoustic device used for examining the function of the organ of hearing. It is designed to measure the individual's ability to hear sounds of different frequencies and intensities. By presenting tones at varying levels, an audiometer can determine the person's hearing thresholds and identify any hearing loss or impairment. This examination helps in diagnosing and monitoring hearing disorders and determining the appropriate treatment options.
9.
The most frequent audiometric examination is determination of thresholds of hearing for pure tones, which is conducted:
Correct Answer
D. By air conduction as well as by bone conduction
Explanation
The correct answer is by air conduction as well as by bone conduction. This means that the most frequent audiometric examination determines thresholds of hearing for pure tones using both air conduction and bone conduction. Air conduction testing involves using headphones to deliver sound directly to the ear, while bone conduction testing involves using a vibrating device placed on the skull to bypass the outer and middle ear and directly stimulate the inner ear. By testing both methods, it provides a comprehensive assessment of a person's hearing abilities.
10.
Normal hearing threshold for specific frequencies looks on a relative audiogram like
Correct Answer
B. Horizontal line
Explanation
The correct answer is a horizontal line. This is because a horizontal line on a relative audiogram indicates normal hearing thresholds across all frequencies. It suggests that the individual has no hearing loss and can hear equally well at different pitches or frequencies.
11.
For examining visual acuity e. g. Snellen’s optotypes are used, to more objective methods belongs:
Correct Answer
D. Landolt rings
Explanation
Landolt rings are used as a more objective method for examining visual acuity. They consist of a ring with a gap or opening in a specific orientation. The person being tested is asked to identify the direction of the opening in the ring. This method helps to objectively measure visual acuity as the person's response is not influenced by factors such as guessing or subjective interpretation.
12.
Which of the series give frequencies that are one octave apart?
Correct Answer
A. 125 Hz, 250Hz, 500 Hz, 1000 Hz
Explanation
The frequencies 125 Hz, 250 Hz, 500 Hz, and 1000 Hz are one octave apart because each frequency is double the previous one. In music, an octave represents a doubling or halving of frequency. So, starting from 125 Hz, when we double the frequency, we get 250 Hz, and when we double it again, we get 500 Hz, and so on. This pattern of doubling the frequency for each subsequent term in the series indicates that the frequencies are one octave apart.
13.
The unit for intensity level of a sound is
Correct Answer
B. Decibel
Explanation
The intensity level of a sound is measured in decibels. Decibel is a unit used to quantify the intensity or loudness of a sound. It is a logarithmic scale that compares the sound pressure level to a reference level. This unit allows us to express a wide range of sound intensities, from the faintest whisper to the loudest rock concert, in a more manageable and standardized manner. Therefore, decibel is the correct unit for measuring the intensity level of a sound.
14.
The threshold audiogram has
Correct Answer
C. The horizontal line corresponds to the left ear
Explanation
The correct answer is that the horizontal line corresponds to the left ear. This means that the frequencies and intensity levels depicted on the horizontal line in the threshold audiogram are specifically related to the left ear. This information is crucial in interpreting the results of the audiogram accurately and understanding the hearing thresholds of the left ear.
15.
The minimum separabile is used
c also correct
Correct Answer
B. For determination of stereoscopic parallax
Explanation
The minimum separable distance refers to the smallest distance at which two points can be perceived as separate entities by the eyes. This ability is crucial for determining stereoscopic parallax, which is the perceived difference in position of an object when viewed from different angles by each eye. By understanding the minimum separable distance, we can design glasses or other visual aids that enhance the perception of depth and create a more realistic 3D effect.
16.
Minimal angle of resolution (MAR) and visual acuity (V) are approx. in the relation:
Correct Answer
C. Log V = - log MAR
Explanation
The given relation states that the logarithm of visual acuity (V) is equal to the negative logarithm of minimal angle of resolution (MAR). This implies that as the visual acuity increases, the minimal angle of resolution decreases. In other words, the higher the visual acuity, the better the ability to distinguish fine details and the smaller the angle required to separate two points.
17.
Velocity of the sound in air is 340 m/s. The vawelength of the harmonic tone of frequecy 1 kHz in air is
Correct Answer
B. 34 mm
Explanation
This question hasnt been answered yet.
18.
Lens refraction capability is expressed by the physical quantity:
Correct Answer
B. Called optical power
Explanation
The correct answer is "called optical power." Optical power is a measure of the lens's ability to bend light and is expressed in diopters. It determines the strength of the lens and is used to correct vision problems. Focal length is related to optical power but specifically refers to the distance between the lens and the point where light converges. Refractive index is a measure of how much a material can bend light, and optical radius is not a commonly used term in optics.
19.
Punctum Remotum is
Correct Answer
C. In infinite distance for a normal eye
Explanation
Punctum Remotum refers to the farthest point from the eye at which an object can be seen clearly without any accommodation. In other words, it is the point at which the eye's lens is fully relaxed and focused for distant vision. For a normal eye, this point is located at an infinite distance, meaning that the eye can see sharply without any effort or adjustment when looking at objects far away.
20.
Minimum separabile
Correct Answer
E. Is eye resolution limit
Explanation
The term "minimum separabile" refers to the eye's resolution limit, which is the smallest distance between two objects that can be distinguished by the human eye. This means that the eye can perceive objects as separate entities as long as they are at least the minimum separabile apart. It is a measure of the eye's ability to resolve details and is an important factor in evaluating color perception.