Question

Человек массой 80 кг стоит на снегу в лыжных ботинках. Длина подошвы каждого ботинка 35 см ,а ширина 12 см . Определите давление ,оказываемое человеком на снег? Во сколько изменится это давление ,если человек встанет на лыжи, длина которых 200 см, а ширина 15 см

Answer 1

P1=mg/2s=80*10/2*0.35*0.12=9523 па=9,52 кПа
Р2=80*10/2*2*0,15= 1333 па=1,3 кПа 

Р1/Р2=9,52/1,3=7,16

УМЕНЬШИТСЯ в 7,16 раз

Answer 2

Calculation of Pressure on Snow

To calculate the pressure exerted by a person standing on snow, we need to divide the force exerted by the person's weight by the area of contact between the person's shoes and the snow.

Given: - Mass of the person: 80 kg - Length of each shoe sole: 35 cm - Width of each shoe sole: 12 cm

First, let's calculate the area of contact between one shoe and the snow. We can assume the shape of the shoe sole to be rectangular.

Area of contact = Length of shoe sole * Width of shoe sole

Area of contact = 35 cm * 12 cm = 420 cm²

Next, we need to calculate the force exerted by the person's weight. The force can be calculated using the formula:

Force = Mass * Acceleration due to gravity

Acceleration due to gravity is approximately 9.8 m/s².

Force = 80 kg * 9.8 m/s² = 784 N

Now, we can calculate the pressure exerted by the person on the snow using the formula:

Pressure = Force / Area of contact

Pressure = 784 N / 420 cm²

To convert cm² to m², we divide by 10,000.

Pressure = 784 N / (420 cm² / 10,000) = 18.67 N/m²

Therefore, the pressure exerted by the person on the snow is approximately 18.67 N/m².

Calculation of Pressure on Snow with Skis

Now, let's calculate the pressure exerted by the person on the snow when they stand on skis.

Given: - Length of each ski: 200 cm - Width of each ski: 15 cm

Similar to the previous calculation, we need to calculate the area of contact between one ski and the snow.

Area of contact = Length of ski * Width of ski

Area of contact = 200 cm * 15 cm = 3000 cm²

Next, we calculate the pressure exerted by the person on the snow using the same formula:

Pressure = Force / Area of contact

The force exerted by the person's weight remains the same, which is 784 N.

Pressure = 784 N / (3000 cm² / 10,000) = 26.13 N/m²

Therefore, the pressure exerted by the person on the snow when standing on skis is approximately 26.13 N/m².

To summarize: - Pressure exerted by the person on the snow with regular shoes: 18.67 N/m² - Pressure exerted by the person on the snow with skis: 26.13 N/m²