Question

мальчик массой 45кг стоит на лыжах. длина каждой лыжи1,5м, ширина 10см. Какое давление оказывает мальчик на снег? Сравните его с давлением, которое производит мальчик, стоящий без лыж.

Answer 1

Давление твердых тел = сила тяжести действ. на тело/ площадь поверхности
( p= Fтяж/S)
Fтяж= mg, где g = 10
Fтяж= 45*10=450 Н
S=ab= 1.5* 1000=1500
p=0.3(давление в лыжах)

Answer 2

Calculation of Pressure

To calculate the pressure exerted by the boy on the snow while standing on skis, we can use the formula for pressure:

Pressure (p) = Force (F) / Area (A)

The force exerted by the boy can be calculated using the formula:

Force (F) = mass (m) * acceleration due to gravity (g)

Given: - Mass of the boy (m) = 45 kg - Length of each ski (l) = 1.5 m - Width of each ski (w) = 10 cm = 0.1 m

First, let's calculate the force exerted by the boy:

Force (F) = m * g

Using the standard value for acceleration due to gravity (g = 9.8 m/s^2):

Force (F) = 45 kg * 9.8 m/s^2 = 441 N

Next, let's calculate the area of contact between the skis and the snow:

Area (A) = 2 * l * w

Area (A) = 2 * 1.5 m * 0.1 m = 0.3 m^2

Now, we can calculate the pressure exerted by the boy on the snow:

Pressure (p) = F / A

Pressure (p) = 441 N / 0.3 m^2 = 1470 Pa

Therefore, the boy exerts a pressure of 1470 Pascal (Pa) on the snow while standing on skis.

Comparison with Standing Without Skis

To compare the pressure exerted by the boy while standing on skis with the pressure exerted while standing without skis, we can calculate the ratio of the two pressures:

Ratio = Pressure with skis / Pressure without skis

From the given information, we don't have the necessary data to directly calculate the pressure exerted by the boy while standing without skis. However, we can still compare the two pressures by considering the area of contact.

When standing without skis, the area of contact between the boy's feet and the ground is likely to be smaller than the area of contact between the skis and the snow. This means that the pressure exerted while standing without skis is likely to be higher than the pressure exerted while standing on skis.

Therefore, we can conclude that the pressure exerted by the boy on the snow while standing on skis is lower than the pressure exerted while standing without skis.

Please note that the actual pressure exerted while standing without skis cannot be determined without additional information about the area of contact between the boy's feet and the ground.