An elevator is moving upward with a speed of 5.8 m/s. 5.3 seconds later, the elevator is still moving upward, but its speed has increased to 19.4 m/s. What is the average acceleration, in m/s2, of the elevator during the 5.3 s interval? Please round your answer to one decimal place.
At one particular moment, a subway train is moving with a positive velocity and positive acceleration. Which of the following phrases best describes the motion of this train? Assume the front of the train is pointing in the positive x direction.
The train is moving faster as it moves forward.
The train is moving forward as it slows down.
The train is moving in reverse as it slows down.
The train is moving faster as it moves in reverse
There is no way to determine whether the train is moving forward or in reverse.
3. An airplane starts from rest at the end of a runway and accelerates at a constant rate. In the first second (i.e, at t = 1.0 s) the airplane travels 21 m. What is the distance of the airplane at the end of 3 seconds? Please round your answer to the nearest whole number (integer).
4. An object moves horizontally with a constant acceleration. At time t = 0 s, the object is at x = 0 m. For which of the following combinations of initial velocity and acceleration will the object be at x = 18 m at time t = 3 s?
v0 = +2 m/s, a = -2 m/s
v0 = +2 m/s, a = +2 m/s
v0 = -2 m/s, a = +2 m/s
v0 = -2 m/s, a = -2 m/s
v0 = +3 m/s, a = + 2 m/s
5. A turtle and a rabbit are to have a race. The turtle’s average speed is 0.9 m/s. The rabbit’s average speed is 9 m/s. The distance from the starting line to the finish line is 1216 m. The rabbit decides to let the turtle run before he starts running to give the turtle a head start. How many minutes, at the maximum, can the rabbit wait before starting to run and still win the race? Please round your answer to the nearest whole number (integer). (Note that 1.0 minute = 60 s)
6. Three runners start at the same place. Shaun runs 4.0 km due east and then runs 1.0 km due west. Mark runs 3.0 km due west. Jeff runs 2.0 km due west and then runs 5.0 km due east. Which of the following is true concerning the displacement of each runner?
Shaun’s displacement equals Mark’s displacement, but Jeff’s displacement is different
Mark’s displacement equals Jeff’s displacement, but Shaun’s displacement is different
Shaun, Mark, and Jeff have the same displacements
Shaun, Mark, and Jeff have different displacements
Shaun’s displacement equals Jeff’s displacement, but Mark’s displacement is different
7. Only one of the following is possible for a moving object. Which one is it?
The velocity is constant at all times, and the acceleration is not zero
The velocity is directed eastward and is increasing, while the acceleration is directed westward
The velocity is directed eastward and is decreasing, while the acceleration is also eastward
The velocity is directed northward and is increasing, while the acceleration is zero
The velocity is directed eastward and is increasing, while the acceleration is also eastward
8. A car that was initially moving at 7 m/s accelerates in a straight-line path at a constant rate
of 6 m/s2. How far will the car travel in 10 seconds? Please round your answer to the nearest
whole number (integer).
A car travels due east at 22 m/s. It makes a turn due south and continues to travel at 22 m/s. What is the change in velocity of the car?
31 m/s, 45° south of west
22 m/s, due east
22 m/s, due south
31 m/s, 45° south of east
A ball is thrown as a projectile at an angle of 30o with the horizontal. The initial velocity of the ball is 32 m/s. What are the maximum height (ymax) and the maximum horizontal distance (Range) of the ball, respectively?
20 m; 114.5 m
16 m; 97 m
17 m; 90.5 m
13 m; 90.5 m
13 m; 78.5 m