Cart is set rolling across a level table, at the same speed on every trial. if it runs into a patch of sand, the cart exerts on the sand an average horizontal force of 6 n and travels a distance of 6 cm through the sand as it comes to a stop. if instead the cart runs into a patch of flour, it rolls an average of 18 cm before stopping. what is the average magnitude of the horizontal force the cart exerts on the flour? 2 n

Astone is thrown with a speed v0 and returns to earth, as the drawing shows. ignore friction and air resistance, and consider the initial and final locations of the stone. which one of the following correctly describes the change δpe in the gravitational potential energy and the change δke in the kinetic energy of the stone as it moves from its initial to its final location? options a.δpe = 0 j and δke = 0 j b.δpe is positive and δke is negative c.δpe = 0 j and δke is positive d.δpe is negative and δke is positive e.δpe = 0 j and δke is negative