Página 133 matematicas 2 travesia secundaria​

1,809.98 lb*m/s^2

Step-by-step explanation:

First, we want to know how much weight of the boulder is projected along the path in which the boulder can move.

The weight of the boulder is:

W = 322lb*9.8 m/s^2 = (3,155.6 lb*m/s^2)

This weight has a direction that is vertical, pointing downwards.

Now, we know that the angle of the hill is 35°

The angle that makes the direction of the weight and this angle, is:

(90° - 35°)

(A rough sketch of this situation can be seen in the image below)

Then we need to project the weight over this direction, and that will be given by:

P = W*cos(90° - 35°) = (3,155.6 lb*m/s^2)*cos(55°) = 1,809.98 lb*m/s^2

This is the force that Samuel needs to exert on the boulder if he wants the boulder to not roll down.