Forces and Motion Forces and Motion ReviewReview

Balanced and Unbalanced Balanced and Unbalanced ForcesForces

Mrs. Bixler-Zalesinsky Mrs. Bixler-Zalesinsky

Use this picture to answer the Use this picture to answer the following questions. following questions.

1. 1.

What forces are acting on the apple What forces are acting on the apple when it is at rest on the books? when it is at rest on the books?

a. gravitya. gravity b. applied b. applied c. normalc. normal d. both a and b d. both a and b

2. 2.

After a student’s force acts on the After a student’s force acts on the objects in the figure to remove the objects in the figure to remove the books quickly and causing the apple books quickly and causing the apple to fall, which object(s) did NOT to fall, which object(s) did NOT accelerated? accelerated?

a. apple a. apple b. booksb. books c. table c. table d. student d. student

3. 3.

When the student’s force acts on When the student’s force acts on the diagram above, the main force the diagram above, the main force acting on the apple, which causes it acting on the apple, which causes it to fall, is which of the following? to fall, is which of the following?

a. gravitational a. gravitational b. frictionalb. frictional c. air resistance c. air resistance d. normal d. normal

4. 4.

When the force of the student acted When the force of the student acted on the figure above, which objects on the figure above, which objects had velocity greater than zero?had velocity greater than zero?

a. tablea. table b. apple b. apple c. booksc. books d. both b and c d. both b and c

5. 5.

A student collects and analyzes A student collects and analyzes data from the motion of the apple data from the motion of the apple from the time it rests atop the from the time it rests atop the books until it is just above the floor. books until it is just above the floor. Create a distance (m) vs. time (s) Create a distance (m) vs. time (s) graph that most closely represents graph that most closely represents the motion of the apple for this brief the motion of the apple for this brief period of time. period of time.

6. 6.

The student collects and analyzes The student collects and analyzes data of the motion of the apple data of the motion of the apple from the time it rests atop the from the time it rests atop the books until it is just above the floor. books until it is just above the floor. Create a speed (m/s) vs. time (s) Create a speed (m/s) vs. time (s) graph that most closely represents graph that most closely represents the motion of the apple for this brief the motion of the apple for this brief period of time. period of time.

7. – 9. Imagine a marble is going to 7. – 9. Imagine a marble is going to roll off of a book on an inclined roll off of a book on an inclined

plane onto a stack of dominos like plane onto a stack of dominos like the picture below. the picture below.

7. 7.

In order to find the force that hit the In order to find the force that hit the domino, you need to know what domino, you need to know what measurements? measurements?

a. mass of the marblea. mass of the marble b. acceleration of the marbleb. acceleration of the marble c. mass of the domino c. mass of the domino d. both a and b d. both a and b

8. 8.

8. To find the acceleration of the 8. To find the acceleration of the marble, you need to know which marble, you need to know which measurements? measurements?

a. mass of the marblea. mass of the marble b. change in the velocity of the b. change in the velocity of the

marblemarble c. time it took to travel c. time it took to travel d. both b and c d. both b and c

9. 9.

To find the velocity of the marble, To find the velocity of the marble, you need to know which you need to know which measurements?measurements?

a. mass of the marblea. mass of the marble b. distance of wood b. distance of wood c. time it took to travelc. time it took to travel d. both b and c d. both b and c

10. 10.

In some situations, friction is In some situations, friction is desirable, which of the following are desirable, which of the following are situations where friction is situations where friction is desirable? desirable?

a. turning car a. turning car b. sleddingb. sledding c. skiing c. skiing d. both b and c d. both b and c

11. 11.

In some situations, the effect of friction is In some situations, the effect of friction is undesirable and needs to be minimized. undesirable and needs to be minimized. In which of the situations listed below In which of the situations listed below would friction be undesirable? would friction be undesirable?

a. moving machine parts rubbing a. moving machine parts rubbing togethertogether

b. walkingb. walking c. warming handsc. warming hands d. braking d. braking

12.12.

In which of the following does In which of the following does torque play a part? torque play a part?

a. opening a flip-top can a. opening a flip-top can b. digging and lifting a shovelful of b. digging and lifting a shovelful of

dirtdirt c. pedaling a bicyclec. pedaling a bicycle d. all of the aboved. all of the above

13.13.

Which of the following parts of a Which of the following parts of a human body does NOT contribute to human body does NOT contribute to maintaining balance? maintaining balance?

a. muscle and jointsa. muscle and joints b. heartb. heart c. inner earc. inner ear d. eyes d. eyes

14. 14.

The difference between speed and The difference between speed and velocity is that velocity includesvelocity is that velocity includes

a. directiona. direction b. timeb. time c. distancec. distance d. weight d. weight

15.15.

Which is an example of kinetic Which is an example of kinetic friction? friction?

friction between a car’s windshield friction between a car’s windshield and the air as you drive into the windand the air as you drive into the wind

friction between your shoes and the friction between your shoes and the ground when you stand stillground when you stand still

friction between a sticky note and the friction between a sticky note and the page of a book as it marks your placepage of a book as it marks your place

friction between your skin and a friction between your skin and a pencil as it rests in your palmpencil as it rests in your palm

16. 16.

A race car travels around a circular A race car travels around a circular track. Explain why the car is track. Explain why the car is accelerating even though the driver accelerating even though the driver maintains a constant speed. maintains a constant speed.

Your foot pushes down on the Your foot pushes down on the accelerator, but you just don’t feel it.accelerator, but you just don’t feel it.

You are constantly changing You are constantly changing direction.direction.

You are speeding up. You are speeding up. You are slowing down You are slowing down

17. 17.

An airplane is flying at 635 miles per An airplane is flying at 635 miles per hour at an altitude of 35,000 feet. It is hour at an altitude of 35,000 feet. It is currently over Kansas and is currently over Kansas and is approximately 16 minutes ahead of its approximately 16 minutes ahead of its scheduled arrival time. What is its scheduled arrival time. What is its speed?speed?

635 miles per hour635 miles per hour 35,000 feet35,000 feet 16 minutes16 minutes Cannot be determined Cannot be determined

18. 18.

Displacement Displacement must be in a particular directionmust be in a particular direction is the change in position of an object is the change in position of an object must be the shortest distance possible must be the shortest distance possible

between two pointsbetween two points all of the above all of the above

19. 19.

The similarity between acceleration The similarity between acceleration and velocity is that they both and velocity is that they both measure themeasure the

rate of change of displacementrate of change of displacement rate of change of velocityrate of change of velocity change over timechange over time both a and bboth a and b

20.20.

If the net force acting on a If the net force acting on a stationary object is zero, then the stationary object is zero, then the object will object will

accelerate in the direction of the accelerate in the direction of the strongest forcestrongest force

remain at restremain at rest begin moving backwardsbegin moving backwards decelerate at a steady rate of speeddecelerate at a steady rate of speed

21.21.

In order to determine if an object is In order to determine if an object is moving, you must observe the moving, you must observe the object in relation to a ___.object in relation to a ___.

a. curved patha. curved path b. moving objectb. moving object c. reference pointc. reference point d. forced. force

Extended ResponseExtended ResponseYou may want to complete your You may want to complete your pre-writing activities outside of pre-writing activities outside of class; however, nothing can be class; however, nothing can be

brought into the test! brought into the test!

22.22.

Michael started piling books on a Michael started piling books on a small table. Eventually the table small table. Eventually the table broke. broke.

Which arrow represents the force of Which arrow represents the force of gravity? (2 pts.) gravity? (2 pts.)

Which arrow represents the force of Which arrow represents the force of the table on the books? (2 pts.) the table on the books? (2 pts.)

Explain why the table eventually Explain why the table eventually broke. (2 pts.) broke. (2 pts.)

23. 23.

Newton’s second law of motion Newton’s second law of motion states the relationship between states the relationship between force, mass, and acceleration as F force, mass, and acceleration as F = ma. According to this law, what = ma. According to this law, what happens to the acceleration of a happens to the acceleration of a given object with constant mass given object with constant mass when the force acting upon it is when the force acting upon it is increased, Explain your answer. (2 increased, Explain your answer. (2 pts.)pts.)