Question

Человек массой 70 кг стоит на снегу в лыжных ботинках длина подошвы каждого ботинка 30 см ,средняя ширина подошвы 10 см . Какое давление оказывает человек на снег ? Во сколько раз уменьшится это давление ,если человек станет на лыжи длина которых 210 см а ширина такая же как средняя ширина подошвы

Answer 1

P=F\S
1) F=mg, т. е. F=70 кг * 9,8 м\с2=686 Н,
2) S=ширина*длина(в метрах) 0,3*0,1 = 0,03 м2
3)P =F\S = 686 Н\0,03 м2 = 22867Па
4) 686 Н\ (площадь2,1*0,1 = 0,21м2)=3267 Па
5)отношение их = 22867Па\3267 Па= в 7 раз уменьшилось

Answer 2

Calculation of Pressure on Snow

To calculate the pressure exerted by a person on the snow, we need to consider the weight of the person and the area over which the weight is distributed.

Given: - Mass of the person = 70 kg - Length of each ski boot sole = 30 cm - Average width of the ski boot sole = 10 cm

To calculate the pressure, we can use the formula: Pressure = Force / Area.

1. Calculate the force exerted by the person: - Force = Mass * Acceleration due to gravity - Force = 70 kg * 9.8 m/s^2 (acceleration due to gravity) 2. Calculate the area over which the force is distributed: - Area = Length * Width - Area = 30 cm * 10 cm

3. Calculate the pressure: - Pressure = Force / Area

Let's calculate the pressure exerted by the person on the snow.

Calculation:

1. Calculate the force exerted by the person: - Force = 70 kg * 9.8 m/s^2 = 686 N

2. Calculate the area over which the force is distributed: - Area = 30 cm * 10 cm = 300 cm^2 = 0.03 m^2

3. Calculate the pressure: - Pressure = Force / Area = 686 N / 0.03 m^2 = 22,866.67 Pa

Therefore, the person exerts a pressure of approximately 22,866.67 Pascal (Pa) on the snow.

Calculation of Reduced Pressure on Snow with Skis

Now, let's calculate how much the pressure will decrease if the person stands on skis with a length of 210 cm and the same width as the average width of the ski boot sole (10 cm).

To calculate the new pressure, we need to consider the new area over which the weight is distributed.

Given: - Length of each ski = 210 cm - Width of the ski = 10 cm

1. Calculate the new area over which the force is distributed: - Area = Length * Width - Area = 210 cm * 10 cm = 2100 cm^2 = 0.21 m^2

2. Calculate the new pressure: - Pressure = Force / Area

Let's calculate the reduced pressure exerted by the person on the snow when standing on skis.

Calculation:

1. Calculate the new area over which the force is distributed: - Area = 210 cm * 10 cm = 2100 cm^2 = 0.21 m^2

2. Calculate the new pressure: - Pressure = Force / Area = 686 N / 0.21 m^2 = 3,266.67 Pa

Therefore, when the person stands on skis, the pressure exerted on the snow is reduced to approximately 3,266.67 Pascal (Pa).

Conclusion:

- When the person stands on the snow in ski boots, the pressure exerted on the snow is approximately 22,866.67 Pa. - When the person stands on skis, the pressure exerted on the snow is reduced to approximately 3,266.67 Pa.

Please note that these calculations are based on the given information and assumptions. The actual pressure distribution may vary depending on various factors such as the condition of the snow, the person's weight distribution, and the flexibility of the ski.