Question

Комната имеет длину 4 м и высоту 3 м. На одной стене комнаты вертикально висит зеркало. Человек стоит на расстоянии 1 м от зеркала лицом к зеркалу. Какой должна быть минимальная высота зеркала, чтобы человек мог видеть находящуюся за его спиной стену в полную высоту (от пола до потолка)? Ответ выразите в см, округлите до целого числа.

Answer 1

Ответ:

Объяснение:

дано L=4 м

H=3 м

a=1 м

h- ?

из подобия треугольников

Н/(L+a)=h/a

h=H*a/(L+a)=3*1/(4+1)=3/5=0,6 м

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ответ h=0,6 м

Answer 2

Calculation of Minimum Mirror Height

To determine the minimum height of the mirror required for a person to see the entire wall behind them, we can use the concept of similar triangles.

Let's consider the following information: - Length of the room: 4 meters - Height of the room: 3 meters - Distance of the person from the mirror: 1 meter

To see the entire wall behind them, the person's line of sight should be parallel to the floor. This means that the person's line of sight should form a right angle with the mirror's surface.

Using similar triangles, we can set up the following proportion:

Height of the mirror / Distance of the person from the mirror = Height of the room / Length of the room

Let's substitute the given values into the proportion:

Height of the mirror / 1 meter = 3 meters / 4 meters

To find the height of the mirror, we can cross-multiply and solve for it:

Height of the mirror = (1 meter * 3 meters) / 4 meters

Simplifying the expression:

Height of the mirror = 3/4 meters

To express the answer in centimeters and round it to the nearest whole number, we can convert meters to centimeters:

Height of the mirror = (3/4 meters) * (100 centimeters / 1 meter) = 75 centimeters

Therefore, the minimum height of the mirror should be 75 centimeters for the person to see the entire wall behind them.