Name: _______________________________________ Date: __________________ Period: _______ Free-Body Diagram Worksheet 1. An 8kg block is being pushed to the right with 15N of force across a table with a coefficient of kinetic friction equal to 0.15. What is the acceleration of the block? ΣFy = N – W = 0 N=W=(m)(g) ΣFx = P – f k = (m)(a) P   k (m)( g ) a=  m 15 N  (0.15)(4kg)(9.81 4kg m ) s 2  2.28 m s2 Answer:__________2.28(m/s2)___________ 2. Hector is walking his dog (Fido) around the neighborhood. Upon arriving at Fidella's house (a friend of Fido's), Fido turns part mule and refuses to continue on the walk. Hector yanks on the chain with a 67.0 N force at an angle of 30.0° above the horizontal. Determine the horizontal and vertical components of the tension force. Fx: 58.0 N Fy: 33.5 N Answers: _______________________________________________ 3. Helen is parasailing. She sits in a seat harness which is attached by a tow rope to a speedboat. The rope makes an angle of 51° with the horizontal and has a tension of 350 N. Determine the horizontal and vertical components of the tension force. Ftension-horizontal: 220 N Ftension-vertical: 270 N (rounded from 272 N) Answers: _______________________________________________ Name: _______________________________________ Date: __________________ Period: _______ 4. At one moment during a walk around the block, there are four forces exerted upon Fido - a 10.0 kg dog. The forces are: Fapp = 67.0 N at 30.0° above the horizontal (rightward and upward) Fnorm = 64.5 N, up Ffrict = 27.6 N, left Fgrav = 98 N, down Resolve the applied force (Fapp) into horizontal and vertical components, then add the forces up as vectors to determine the net force. Fapp-horizontal: 58.0 N, right Fapp-vertical: 33.5 N, up Fnet: 30.4 N, right nswers: _______________________________________________ 5. Austin and John, linebackers for the varsity football team, delivered a big hit to the halfback in last weekend’s game. Striking the halfback simultaneously from different directions with the following forces: FAustin = 1230 N at 53° FJohn = 1450 at 107° Determine the resultant force applied by Austin and John to the halfback. (The directions of the two forces are stated as counter-clockwise angles of rotation with East.) 2390 N at 82° N of E Answers: _______________________________________________ Name: _______________________________________ Date: __________________ Period: _______ 6. A pack of three Artic wolves are fighting over the carcass of a dead polar bear. A top view of the magnitude and direction of the three forces is shown in the diagram to the right. a. Determine the resultant or net force acting upon the carcass. b. Determine the acceleration of the 750-kg polar bear carcass. a. 190 N at 23° south of east (or 337°) b. 0.25 m/s/s Answers: _______________________________________________ 7. Katniss is on Fall Break and pulling her 21-kg suitcase through the airport at a constant speed of 0.47 m/s. She pulls on the strap with 120 N of force at an angle of 38° above the horizontal. Determine the normal force and the total resistance force (friction and air resistance) experienced by the suitcase. Fresistance: 95 N Fnorm: 130 N (rounded from 132 N) Answers: _______________________________________________ Name: _______________________________________ Date: __________________ Period: _______ 8. Ben Laborin works for the Lee bookstore during the summer months to help prepare for Fall sales. Books from one supplier are shipped to the school in large crates equipped with rope handles on all sides. On one occasion, Ben momentarily pulled with a force of 692 N at an angle of 36.0° above the horizontal to accelerate a 112-kg crate of books. The coefficient of friction between the crates and the vinyl floor is 0.548. Determine the acceleration experienced by the crate. 1.62 m/s/s Answers: _______________________________________________ 9. Lon Mauer is cleaning up the driveway after mowing the grass. He exerts a sudden downward force of 56.8 N at a constant angle of 54.7° below the horizontal in order to accelerate his 1.05-kg broom from rest. The coefficient of friction between the broom bristles and the driveway is 0.567. Determine the rate of acceleration of the broom. 0.670 m/s/s Answers: _______________________________________________