1. 2-D Force Problems

2. 7 kg 2N 3N 8N Find the direction and magnitude of the acceleration of the box.

3. Sally pushes an old fashioned lawnmower at a constant speed of 3 m/s. She pushes with 100 N at an angle of 65°. Draw a FBD and find the vertical and horizontal components of her push. How much friction must there be?

4. Find the horizontal force on the box. NO FRICTION Draw FBD Find the vertical component of the pull of the rope.

5. If the box has a mass of 8 kg Find its acceleration Find its weight Find the normal force that the ground pushes up.

6. Two dimensional forces must be summed up in the x direction alone, the y direction alone, then finally connected head to tail and added with the pythagorean theorem

7. Adding Multiple Forces that are not at right angles 2 Possible Strategies: Graphical method: 1. Draw the vectors to scale. 2. Connect the vectors head to tail. 3. Resultant goes from head of first to the tail of the last. Analytical method: 1. Use trigonometry to resolve all vectors into X and y components. 2. Add all the x vectors to each other., then add all the y vectors to each other. 3. Find the resultant with the Pythagorean Theorem.

8. These three cartoon creatures are trying to pull a statue. Graphically find the resultant vector if: The Ant applies 100N@220 0 The Penguin 200N@240 0 Jackie Chan 300N@308 0 Which vector is which? Will it move, and which way will it go ? 0 90 180 270

9. For graphical vector addition to work, the arrows must be drawn at exactly the right angle using a protractor and must be drawn to scale (proportionally) using a ruler. Check this drawing with a ruler and protractor The Ant applies 100N@220 The Penguin 200N@240 Jackie Chan 300N@308

10. 200N 300N 100N R=240N@270 0 Combining the vectors “tip to tail”, regardless of the order, gives us the resultant. How can we graphically find how big this resultant is?