Drawing method:
(1) 60N is represented by 1cm. First draw a 3cm vertical downward line segment, which represents the vertical force f of 180N.
(2) Make a line segment with a horizontal length of 4cm 1 to the right to represent the horizontal component f1;
(3) connect f1f;
(4) Let F 1F pass through the parallel line of O, and F 1 pass through the parallel line of F, and the two lines intersect at F;
(5) Connect OF2, the size and direction of OF2 is the size and direction of another component.
Evaluation:
F2= root number (F 2+F 1 2) = root number (1802+240) = 300 n.
tanα=240/ 180=4/3，α≈53
That is, the other component is 300N, and the direction is 53 to the left.
18.( 10 minute) Place a homogeneous and smooth ball with a gravity of g between the inclined plane and the baffle. When the baffle is vertical and inclined (as shown in the figure), what is the pressure ratio of the ball to the baffle in both cases?
The ball is subjected to three forces:
Gravity g, downward;
Inclined plane supporting force f, vertical inclined plane inclines upward;
Baffle support force n, vertical baffle.
(1) When the baffle is vertical:
Force balance parallel to the inclined plane: N 1cosα=Gsinα, N 1=Gtanα.
(2) When the baffle is perpendicular to the inclined plane:
Force balance parallel to the inclined plane: N2=Gsinα.
n 1:N2 =(gtanα):(gsinα)= 1:cosα