Ch.1,2 & 3 Review Test

Multiple Choice

1. After a rock that is thrown straight up reaches the top of its path and is starting to fall

back down, neglecting air resistance its acceleration is

  1. greatest when it was at the top of its trajectory
  2. least when it was at the top of its trajectory
  3. remains the same during flight

2. A ball is thrown straight up at 50 m/s . At the top of its path its velocity is

  1. 0 m/s
  2. about 5 m/s
  3. about 50 m/s
  4. impossible to tell

3. If a projectile is fired straight up at a speed of 70 m/s, the total time to return to its

starting point is about

  1. 1 second
  2. 7 seconds
  3. 70 seconds
  4. 14 seconds
  5. not enough information to estimate

4. When are the equations of kinematics valid ?

  1. When acceleration is zero
  2. When velocity is constant
  3. When time is constant
  4. When acceleration is constant

5. Suppose a object dropped off a tall building was equipped with a speedometer on a

planet whose g = 20 m/s2, its speed reading would increase each second by

  1. about 20 m/s
  2. about 10 m/s
  3. about 9.8 m/s
  4. none; as laws are different for other planets

6. A Vector would have equal x and y components, when 

  1. zero
  2. 450
  3. 900
  4. they can never be equal

7. The components of a vector can be greater than the vector itself. (True or False)

8. If a body changes its velocity by 24 m/s every second its acceleration is ______

9. If the slope of a velocity – time graph is parallel to the x-axis then acceleration is ____

10. The slope of a distance – time graph gives the ______

11. If the slope of a distance - time graph is parallel to the x-axis then the speed is ___

12. If the slope of a distance - time graph is a straight line is not parallel to the x-axis then

the acceleration is ______

13.The diagram below shows a projectile moving with speed v at the top of its trajectory.

V

Ground

Which vector best represents the velocity vector of the projectile in the position shown?

(a)(c)

(b)(d)

14.Which value of would result in the ball traveling the maximum height?

(a) (c)

(b) (d)

Suppose you are standing in a bus that travels along a straight road at 100 km/hr, and you hold a ball still above you. Q 15 - 19

15. Then relative to the bus, the velocity of the ball is

a. more than 100 km/hr

b 0 km/hr

c less than 100 km/hr

d equal to 100 km/hr.

16. Relative to the road, the velocity of the ball is

  1. more than 100 km/hr
  2. 0 km/hr
  3. less than 100 km/hr
  4. equal to 100 km/hr.

17. Suppose you drop the ball, while it is falling, and relative to the road, the

ball still has a horizontal velocity of

  1. more than 100 km/hr
  2. 0 km/hr
  3. less than 100 km/hr
  4. equal to 100 km/hr.

18.This means that the ball will strike the floor at a place directly

  1. behind you
  2. at your feet right below your hand
  3. somewhere in front of you
  4. it will fly out of the window.

19. Relative to you the ball drops

  1. the same way as if the bus were at rest
  2. is dependent on the velocity of the bus
  3. cannot be determined with information given.
  4. It simply wont fall

20. If a projectile has an initial velocity of 14.1 m/s and is launched at a 450 angle at the

top of its path, its instantaneous velocity is about

(a) 14.1 m/s

(b)–14.1 m/s

(c)10 m/s

(d)0 m/s

(e)cannot be determined

21. A cannonball is launched from the ground at an angle of 60 degrees above the

horizontal with a speed of 40 m/s. Neglecting air resistance the ball will land on the

ground with a speed of ______.

(a) 40 m/s

(b)30 m/s

(c)20 m/s

(d)10 m/s

(e)0 m/s

Q 22-25; Suppose you drop a marble off the Empire state building in New York City. Ignoring air resistance answer questions

22.What is the velocity of the marble after 1 second?

(a) 9.8 m/s

(b) 1 m/s

(c) 4.9 m/s

(d) 19.6 m/s

23.What is the velocity of the marble after 3 seconds?

(a) 3 m/s

(b) 9.8 m/s

(c) 15.7 m/s

(d) 29.4 m/s

24.Approximately how far did the marble fall in 2 second?

(a) 1 m

(b) 20 m

(c) 10 m

(d) 15 m

25.Approximately how far did the marble fall in 4 seconds?

(a) 45 m

(b) 40 m

(c) 20 m

(d) 80 m

Free Response Problems

  1. a) A stone dropped from a cliff on to a river below and a splashes into the water 3.9 sec later. Determine the height of the cliff.

(b) A cyclist is traveling due North and covers the first part of her trip in 35 minutes at a velocity of 6.1 m/sec and the second part of her trip in 42 minutes at a velocity of 3.3 m/sec. Find her average velocity (both magnitude and direction. (Hint: convert minutes to seconds)

2. Michael Jordan jumps a height of 1.2 m above the ground

Determine

  1. How much time does he take to reach maximum height?. What is his hang

time?

b. With what velocity (both magnitude and direction) does he hit the ground?

c. What was his initial velocity?

d. Could he jump higher on the moon? Would his hang time be greater?

3. A plane at an altitude of 255 m is traveling at 125 m/s and drops a care package to inhabitants of a remote island in the South Pacific.

(a)How long will it take the package to hit the ground?

(b)How far before the target should the pilot release the package?

(c)What velocity does the package hit the ground? (consider both “x” and “y” velocities to estimate resultant)

(d)With what angle does the package hit the ground? (use the inverse trigonometric function)

4. In the graph provided below add two vectors in the first and third quadrant

A
B
Vector
A / Values / Vector
B / Values / Vector
A + B / Values
x Compon / x Compon / x Component
y Compon / y Compon / y Component
Magnitude / Magnitude / Magnitude
Direction / Direction / Direction

Complete the table above and be sure to graph the resultant.