9:07AM Sat Mar 9 eoe T@C59% @) & webassign.net PREVIOUS ANSWERS WEBASSIGNALGPHYS1 2.1.001. ASK YOUR TEACHER PRACTICE ANOTHER A truck travels due east for a distance of 1.4 km, turns around and goes due west for 6.6 km, and finally turns around again and travels 2.7 km due east. 1. [2/3 Points] (a) What is the total distance, in kilometers, that the truck travels? (07 v (b) What are the magnitude (in km) and direction of the truck's displacement? magnitude b Displacement is the change in position, that is, the difference between the initial and final position. km direction west c Supporting Materials .| Physical Constants Submit Answer 2. [-/2 Points] WEBASSIGNALGPHYS1 2.1.002. ASK YOUR TEACHER Find the following (in m) for the path in the figure below. 0 2 4 6 8 10 12 x(m) (a) the total distance traveled [ = (b) the displacement from start to finish C__Jr Supporting Materials | Physical Constants 3. [-/2 Points] WEBASSIGNALGPHYS1 2.1.003. ASK YOUR TEACHER Two soccer players kick a soccer ball back and forth along a straight line. The first player kicks the ball 15 m to the right to the second player. The second player kicks the ball to the left weakly; it only moves 1.7 m before stopping. (Consider the right to be the positive direction. Where applicable, indicate the direction with the sign of your answer. All distances are in meters.) (a) What is the total distance that the ball moved? [ = (b) At the end, what is the displacement of the ball (from the first player)? [ = Supporting Materials | Physical Constants Submit Answer 9:07 AM Sat Mar 9 . . . @ 59% webassign.net Submit Answer 6. [2/3 Points] DETAILS PREVIOUS ANSWERS WEBASSIGNALGPHYS1 2.5.001.TUTORIAL. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER A remote controlled toy car starts from rest and begins to accelerate in a straight line. The figure below represents "snapshots" of the car's position at equal 0.5 s time intervals. (Assume the positive direction is to the right. Indicate the direction with the sign of your answer.) 1=0s t=0.5s 1= 1.0s 1 = 1.5 s 1= 2.0 s O O O O 0m 0.1 m 0.4 m 0.9 m 1.6 m (a) What is the car's average velocity (in m/s) in the interval between t = 0.5 s to t = 1.0 s? 0.6 m/s (b) Using data from t = 0.5 s to t = 1.5 s, what is the car's acceleration (in m/s ) at t = 1.0 s? 0.4 X Recall that the definition of average acceleration is the change in velocity divided by the change in time. What is the initial velocity? What is the final velocity? Be careful about the change in time as well-if you measure velocities at "midpoints" within two separate intervals, what is the separation between those midpoints? m/s (c) Is the car's speed increasing or decreasing with time? increasing O decreasing O constant not enough information Supporting Materials Physical Constants Additional Materials Tutorial Submit Answer 7. [2/2 Points] DETAILS PREVIOUS ANSWERS WEBASSIGNALGPHYS1 2.5.012. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER11. [0/1 Points] PREVIOUS ANSWERS HRW10 2.P.053.SSM. ASK YOUR TEACHER PRACTICE ANOTHER A key falls from a bridge that is 54 m above the water. It falls directly into a model boat, moving with constant velocity, that was 10 m from the point of impact when the key was released. What is the speed of the boat? X m/s Constant-acceleration equations, for vertical motion. For the key, you know the initial velocity, the (downward) displacement, and the (downward) acceleration, and you want the time. Then you know the time the boat has to move the given distance at constant velocity. Submit Answer 9:07AM Sat Mar 9 T@C59% @) RV EIS (e [a NI} B 2AGHWCh2.. ASK YOUR TEACHER PRACTICE ANOTHER 13. [5/6 Points] PREVIOUS ANSWERS HRW10 2.P.015.GO. A particle's position is given by x = 2 11t + 22 (where t is in seconds and x is in meters). (a) What is its velocity at t = 1 s? (Indicate the direction with the sign of your answer.) -7 m/s (b) Is it moving in the positive or negative direction of x just then? O positive o negative O neither v (c) What is its speed just then? 7 m/s (d) Is the speed increasing or decreasing just then? O increasing decreasing O neither (Try answering the next two questions without further calculation.) (e) Is there ever an instant when the velocity is zero? If so, give the time t; if not, enter NONE. & s (f) Is there a time after t = 3.8 s when the particle is moving in the negative direction of x? If so, give the time t; if not, enter NONE. The velocity function is the time derivative of the position function. The sign of the velocity vector gives the direction of travel on the x axis. The particle stops when the velocity is zero. s 3 GO Tutorial Submit Answer 14. [1/2 Points] ASK YOUR TEACHER PRACTICE ANOTHER PREVIOUS ANSWERS OSUNIPHYS1 3.1.P.027. The position of a particle moving along the x-axis is given by x(t) = 4.2 2.5t m. (Assume t is in seconds.) (a) At what time (in s) does the particle cross the origin? (o v s (b) What is the displacement (in m) of the particle between t = 3.2 s and t = 6.4 s? (Indicate the direction with the sign of your answer.) Submit Answer GRRPHYS2 2.P.038. ASK YOUR TEACHER You are driving your car along a country road at a speed of 26.0 m/s. As you come over the crest of a hill, you notice a farm tractor 25 m ahead of you on the road, moving in the same 15. [-/3 Points] direction as you at a speed of 11.0 m/s. You immediately slam on your brakes and slow down with a constant acceleration of magnitude 7 m/sz. Will you hit the tractor before you stop? O Yes O No How far will you travel before you stop or collide with the tractor? m If you stop, how far is the tractor in front of you when you finally stop? (If you instead collide, enter 0 below.) m Submit