Motion in one directionOnline version To consolidate the core topics about accelerated motion by Julio Fajardo 1 What acceleration does an object have at the peak of the upward motion? a - 9.81 m/s2 b zero c + 9.81 m/s2 d none of the above 2 The time it takes an object to move straight upward compared to that required to fall from its maximum height is a much less b much greater c exacty the same d zero 3 A stone is thrown upward with an initial velocity of + 10 m/s. Its final velocity when it is returning to the thrower´s hand is a zero b + 10 m/s c - 10 m/s d * 20 m/s 4 Jason accidentally falls from a very tall tree. What is Jason´s velocity after 4 seconds of falling freely? a - 9.81 m/s2 b + 9.81 m/s c + 39.2 m/s d - 39.2 m/s 5 As an object reaches the maximum height, it is true that a its velocity increases randomly b its velocity stays the same c its velocity decreases randomly d its velocity decreases at a steady rate 6 A baseball is thrown straight upward. What is the ball´s acceleration midway between the initial position and the maximum height? a g upward b one-half of g, downward c one-half of g, upward d g downward 7 Which of the statements is true of acceleration? a Acceleration always has the same sign of displacement. b Acceleration always has the same sign of velocity. c The sign of acceleration depends on both, the direction of motion and how the velocity changes d Acceleration always has a positive sign 8 A particle travels along a curved path between points P and Q as shown. The displacement of the particle does not depend on a the location of P b the location of Q c the distance traveled from P to Q d The shortest distance between P and Q 9 For which one of the following situations will the path equal the magnitude of the displacement? a A toy train is traveling around a circular path b A ball is rolling down an inclined plane c A train travels 5 miles East beore it stops. It then travels 2 miles West d A ball on the end of a string is moving in a vertical circle 10 A car is traveling in a straight line covering a total distance of 90.0 miles in 60.0 seconds. Which of the following statements concerning this situation is necessarily true? a The velocity of the car is constant. b The acceleration of the car must be non-zero. c The first 45 miles must have been covered in 30.0 minutes d The average velocity of the car is 90 miles per hour in the direction of motion 11 Starting from rest, a particle confined to move along a straight line is accelerated at a rate of 5.0 m/s2. Which of the following statements accurately describes the motion of this particle? a The particle travels 5.0 m during each second. b The particle travels 5.0 m only during the first second. c The speed of the particle incrases by 5.0 m/s during each second d The speed of the particle will be proportional to the distance the particle travells 12 Two objects A and B accelerate from rest with the same constant acceleration. Object A accelerates for twice as much time as object B, however. Which one of the following statements is true concernng these objects at the end of their respective periods of acceleration? a A will travel twice as far as B b A will travel four times as far as B c A will travel eight times further than B d A will be moving four times faster than B 13 An object moving along a straight line is decelerating. Which one of the follosing statements concerning the object´s acceleration is necessarily true? a The value of acceleration is positive. b The direction of the acceleration is in the same direction as displacement. c An object that is decelerating has a negative acceleration. d The direction of the acceleration is in the same direction opposite to that of the velocity 14 A body initially at rest is accelerated at a constant rate for 5 seconds in the positive direction of X. If the final speed of the body is 20 m/s, what was the body´s acceleration? a 0.25 m/s2 b 2.0 m/s2 c 4 m/s2 d 9.8 m/s2 15 A ball is dropped from rest from a tower and strikes the ground 110 m below. Approximately how many seconds does it take the ball to strike the ground after being dropped? a 2.50 seconds b 3.50 seconds c 4.74 seconds d 12.5 seconds