Question

Help with force!

Answer 1

a) weight= force x sin (angle)
b) against= force x cos (angle)

Answer 2

^ thanks!! i'll let you know what answers i get :)

Answer 3

ok

Answer 4

weight = 139
force = 428
(both rounded of course)

Answer 5

hrm that is not correct.

Answer 6

super huge numbers.

Answer 7

The sum of forces in the x-direc are the component of weight in the x and friction:
F_x = W*sin(12) - F_friction
The frictional force is 430. F_x is 0 since the car is not moving. Solve for W. W = 2068 lbs

The sum of forces in the y-direc are the component of the weight in the y and the normal force:
The sum of the forces in the y is 0 because the car is not sinking or floating
F_y = F_Normal - W*cos(12)
F_Normal = 2068 *cos(12) = 2023 lbs. ---this is the force the car exerts on the driveway.

Answer 8

ooki they give an example in the book.
a) the magnitutde of the part of the force w that causes the car to roll down the driveway is
|u|=component of w along u

Answer 9

aah, sorry I didn't see you had already posted :P

Answer 10

these last applies to the first too ;)

Answer 11

soo how does this look with my given numbers?

Answer 12

F_x = W*sin(18) - F_friction
The frictional force is 450. F_x is 0 since the car is not moving. Solve for W. W = 1456 lbs

The sum of forces in the y-direc are the component of the weight in the y and the normal force:
The sum of the forces in the y is 0 because the car is not sinking or floating
F_y = F_Normal - W*cos(12)
F_Normal = 1456*cos(18) = 1385 lbs. ---this is the force the car exerts on the driveway.

Answer 13

the force is 1385
and the weight is 1456?

Answer 14

yay that's right :) thanks so much!!

Answer 15

(how do we do we find out w*w?)