1. The normal force on an extreme skier descending a very steep slope (Fig. 4-42) can be...

Question:

1. The normal force on an extreme skier descending a very steep slope (Fig. 4-42) can be zero if

(a) His speed is great enough.
(b) He leaves the slope (no longer touches the snow).
(c) The slope is greater than 75°.
(d) The slope is vertical (90°).
2. To pull an old stump out of the ground, you and a friend tie two ropes to the stump. You pull on it with a force of 500 N to the north while your friend pulls with a force of 450 N to the northwest. The total force from the two ropes is
(a) Less than 950 N.
(b) Exactly 950 N.
(c) More than 950 N.