Practice Exam 1

PHY 1 5 1 0 Midterm Exam 1 • Q. Ryan 2 Part I. Multiple Choice [32 points total] Circle the correct answer to each question. 8 questions, 4 points each 1. What are the overall dimensions of the formula for the area of a circle ! ! ! ? A. [ ! ] B. [ ! ] ! C. ! ! D. ! [ ! ] ! E. ! ! ! 2. The graph below shows the velocity vs. time for a train moving along a straight track. The graph shows that during the time shown the train… I. Always moves in the same direction II. Reverses direction during its motion III. Has both a positive and a negative acceleration A) Only one of the statements is correct B) Statements I and II are correct C) Statements I and III are correct D) Statements II and III are correct E) All three statements are correct 3. A projectile is launched from the origin of a coordinate system with initial velocity v 0 at angle θ 0 from the horizontal (0 < θ 0 < 90°). At the instant when the projectile is at the highest point of its trajectory, the displacement, velocity, and acceleration vectors are r , v, and a ( bold symbols denote vectors ). Which statement is true? Hint: draw a diagram. A. r is parallel to v . B. r is perpendicular to v . C. v is parallel to a . D. v is perpendicular to a . E. r is perpendicular to a .

PHY 1 5 1 0 Midterm Exam 1 • Q. Ryan 3 4. The velocity of a particle moving along the x -axis is given by ! ( ! ) = ! ! + !" , where t is time in seconds. We define our coordinate system such that for t = 0, the initial position is x 0 = 0 and the initial velocity is v 0 . Which expression describes the position of the particle as a function of time? A. ! ! = ! ! ! + ! ! ! ! ! B. ! ! = ! ! ! + ! ! ! ! C. ! ! = ! ! ! + ! ! ! ! D. ! ! = ! ! ! + ! ! ! ! E. none of the above 5. What is the direction of the vector given by A − B + C ? A. ↑ Up B. ↓ Down C. ← Left D. → Right E. ↖ Up and Left 6. A car drives clockwise around a circular racetrack at a steady speed. At the instant when the car is located at the position indicated by the dot: A. the car’s acceleration points north B. the car’s acceleration points south C. the car’s acceleration points east D. the car’s acceleration points west E. none of the above N S E W