A sled weighs 100 N.It is held in place on a frictionless 30° slope by a rope attached to a stake at the top;the rope is parallel to the slope.What is the normal force acting on the sled?
A) 94 N
B) 87 N
C) 50 N
D) 34 N

Question

Quizplus · Accepted Answer

The normal force is perpendicular to the surface and acts to counteract the weight of the object. Since there is no friction, the force of the rope only acts to keep the sled in place and does not affect the normal force. To find the normal force, we need to resolve the weight force into two components: one parallel to the slope and one perpendicular. 
The component of the weight force perpendicular to the slope is given by: 
F(perpendicular) = W * cos(θ) 
= 100 N * cos(30°) 
= 86.6 N

Therefore, the normal force is equal and opposite to F(perpendicular), and its value is approximately 87 N (closest to B).

A Sled Weighs 100 N