The weight of a person is 40o N. He exerts 400 N/m² if he stand with both
feet find its area

​

1 m²

Explanation:

Applying,

P = F/A Equation 1

Where P = Pressure, F = Force, A = Area

Make A the subject of the equation

A = F/P Equation 2

From the question,

Given: F = 400 N, P = 400 N/m²

Substitute these values into equation 2

A = 400/400

A = 1 m²

Hence the area of the person is 1 m²

the temperature in kelvin of 2.0 dm3 of an ideal gas is doubled and its pressure is increased by a factor of four. what is the final volume of the gas

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.