Question

a) Draw a picture

b) Identify all external forces acting on the system

c) Choose an orientation of a coordinate system and draw a free body diagram

d) Resolve each force into its components. If the magnitude and/or direction of a force are unknown, use symbols to represent them

For each problem below do the above:

1) A Box (35kg) slides down a straight tramp that is included at 20 degrees to the horizontal. The box starts at rest and increases speed as it slides down the ramp. a) Use the box s the system and a horizontal/vertical coordinate system. b) Use the box as the system and use a coordinate system parallel and perpendicular to the ramp.

2)An object is tied to a string and swung in a vertical plane like a pendulum choose the object as a system at the point where the string makes a 27° angle left of the vertical

3)Consider a person holding a ball as shown above. The weight force on the ball is shown (50 lb=222 N). Assume that the muscle makes a 5° angle with the vertical. a) Choose the ball as the system b) Choose the hand and lower arm as the system

4) You stand on the first step of a ladder that is leaning against a vertical wall the base of the latter makes a 40° angle with the horizontal floor. Choose the ladder as a system

Answer 1