Question

What is the average momentum of an avalanche that moves a 40-cm-thick layer of snow over an area of 100 m by 500 m over a distance of 1 km down a hill in 5.5 s? Assume a density of 350 kg/m³ for the snow.

a) 7.7 x 10^7 kg m/s
b) 8.8 x 10^7 kg m/s
c) 9.9 x 10^7 kg m/s
d) 1.1 x 10^8 kg m/s

Answer 1

The average momentum of the avalanche is 9.9 x 10⁷ kg m/s.

Step-by-step explanation:

To calculate the average momentum of an avalanche, we first need to calculate the total mass of the snow moved. The volume of the snow is given by the product of the thickness, area, and distance (40 cm x 100 m x 500 m x 1000 m).

Converting this volume to mass using the density, we get 140 million kg.

The momentum is then calculated by multiplying the mass by the velocity, which is the distance divided by the time (1 km / 5.5 s).

This gives us a momentum of 9.9 x 10⁷ kg m/s.

Therefore, the correct answer is option c) 9.9 x 10⁷ kg m/s.