1. Newton's 2nd Law stipulates that "the sum of all forces acting on an object are equal to the mass times the acceleration of that object." Given the force diagram below, calculate the acceleration of the object (both magnitude and direction). The object is the smiley face, which has a mass of 12.6 kg (it's a very heavy smiley face). FPush = 36.2 N %3D Fg = Weight

1.There is a falling object, whose mass is A [kg] and experiences a force (its own weight) equal numerically to A times 9.81. The object starts from rest and the air causes a retarding force numerically equal to B times its velocity. a)Find general expression for velocity as a function of time, and draw its graph. b)Evaluate velocity for t=C (s) Depending on your value of R choose A B R 0 1 2 6 8 0.180 0.200 0.220 Font C 4 5 6

3. An object with a mass of 1500 g (grams) accelerates 10.0 m/s” when an unknown force is applied to it. What is the amount of the force?

6. Two blocks, with masses shown are pulled up a ramp by a pull force P. The kinetic friction coefficient between each block and the ramp is µg = 0.40. The blocks start from rėst and speed up the ramp. They reach a speed of 0.85 m/s after 4.00 s. 4.0 kg a) Draw FBDS of both masses. Write down correct NII equations. Find the magnitude of the tension in the string connecting the two blocks. 6.0 kg 30°

2.  A chain consists of identical links, each with a mass of 2.5 kg. You grab the top link and hold the chain at rest so that it hangs vertically.    a)  Draw a free body diagram of the bottom three links (labeled 1, 2, 3). Label all forces and use double subscript notation to denote which object exerts the force and which object is experiencing the force.   b)  Find the magnitude of the force exerted on link 1 by link 2, in Newtons.   c)  Find the magnitude of the force exerted on link 2 by link 3, in Newtons.

6. A horizontal pull force of 35 N is required to just start a 6 kg box moving across a horizontal concrete floor. a) Draw the free-body diagram of the box, showing all of the forces acting on the box. b) What is the coefficient of static friction,μs, between the box and floor? c) The 35 N pull force continues, but now that the box is moving, it accelerates at constant a = 0.6 m/s². What is the coefficient of kinetic friction,μk?

Box A, weighting 60 N, is placed on a table tilted at angle of 15˚. Another box, B, weighing 40N, is placed on top of A. Both boxes are at rest.A) Draw the free-body diagram for box B. What is the frictional force exerted on A by B? B) Draw the free-body diagram for box A. What is the frictional force exerted on A by the table?

MCQ 4. The first of two identical boxes of mass m is sitting on level ground. The second box is sitting on a ramp that makes a 20° angle with the ground. The normal force of the level ground on the first box is NL; the normal force of the ramp on the second box is NR. Which statement is correct? a. NR= NL = mg. b. N₁ mg; NR= mg sin 20°. C. NL = mg; NR = mg cos 20°. d. Nr.= mg; NR= -mg cos 20°. e. NR=-NL = -mg.