What should a graph of the velocity vs time look like if it shows an object moving to the left at a constant velocity? Select one: O An upwards curved parabola. O A downwards curved parabola. O A straight line with zero slope that is below the x-axis. O A straight line sloping downward. O A straight line sloping upward. O A straight line with zero slope that is above the x-axis.

Your roommate drops a tennis ball from a third-story balcony. It hits the sidewalk and bounces as high as the second story. Draw a motion diagram, using the particle model, showing the ball’s velocity vectors from the time it is released until it reaches the maximum height on its bounce.

A particle travels along the +x axis. At t = 0 s, its velocity is 10.0 m/s and its acceleration is -2.0 m/s^2.  Question A: Which of the following statements is true?           1. The particle will slow down and eventually come to a complete stop           2. The particle cannot have a negative acceleration and be moving in the positive x direction           3. The particle will continue to move in the positive x direction, slowing but never coming to a complete stop.           4. The particle will slow down, stop momentarily, then speed up in the x- direction.  Question B: At what time will the particle be stopped?           1. t = 5.0 s          2. t = -5.0 s          3. t = -0.2 s          4. The particle does not ever stop  Question C: What is the particle's displacement from its initial position at t = 10.0 s ?  Please Answer questions A, B, and C

You travel from point A to point B in a car moving at a constant speed of 70 km/h. Then you travel the same distance from point B to another point C, moving at a constant speed of 90 km/h. Is your average speed for the entire trip from A to C 80 km/h? Explain why or why not.

15. A runner runs one lap on a 400 m oval in 50 s (i.e. he returns to his starting point in 50 s). What is the magnitude of his average velocity for this 50 s interval? 4.0 m/s 6.0 m/s     8.0 m/s 0.80 m/s zero 14. The magnitudes of two vectors  A and  B are 13 units and 8 units, respectively. What are the largest and smallest possible values for the magnitude of the resultant vector R = A +B ? largest  units smallest  units

A velocity can be negative based on your coordinate system. Is it possible to have a negative speed? Why/why not?

2. The velocity of a particle is given by v = {14t?î+ (4t + 3)j + 6t³k} m/s, where t is in seconds. If the particle is at the origin when t = 0, determine the magnitude of the particle's acceleration when t = 3 s. Also, what is the x, y, z coordinate position of the particle at this instant?

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Can an object have a negative acceleration and be speeding up? If so, describe a possible physical situation and a corresponding coordinate system. If not, explain why not.