Mr. Rogers' Honors Physics

Syllabus 1st Quarter 2nd Quarter 3rd Quarter 4th Quarter
2D Force(5)
2D Motion(6)

Rotation-- Chapter 8

Relavance: rotating equipment is ubiquitous (found everywhere). It includes race cars, ceiling fans, kitchen blenders, and many different types of industrial equipment. Knowing something about rotation is helpful in many jobs as well as in many of life's experiences.

SC Standards :


P-2.9 Explain how torque is affected by the magnitude, direction, and point of application of force.
P-2.10 Explain the relationships among speed, velocity, acceleration, and force in rotational systems.


Practice Test Study Guide


Essential Question: How is rotational motion similar to linear motion?

Rotational Motion Basics

  1. State the rotational equivalents of the linear quantities

    mass, linear inertia...m moment of inertia........I
    displacement............x angle..........................q
    velocity.....................v = Dx /Dt angular velocity..........w = Dq /Dt
    acceleration.............a = Dv /Dt angular acceleration...a = Dw /Dt
    force.........................F torque.........................t
  2. Indicate which rotational quantities are vectors and which are scalars.

  3. State that, by using the right hand thumb rule, rotational vectors can be represented as arrows where the length is proportional to the magnitude and the arrow head represents the direction.

  4. By looking at the arrows representing rotational velocity and acceleration, determine if an object's rotation is speeding up or slowing down.
  5. speeding up: directions match

    slowing down: directions are opposites

  6. Convert between various methods of expressing rotational velocities. ω, RPS, RPM (note: RPS can also be called angular frequency). Relevance: of the 3 expressions, RPM rating will be found on any motor or machine that rotates. RPM is key to the performance of any of these real-world devices.

Homefun (formative/summative assessment): Read sections 8.1, find an electrical device that rotates such as a motor or fan and record the number. Is it evenly divisible by 60?


Formative Assessment: Physics Investigation

Research Question  
Data, Calculations  

Follow up Questions




Essential Question: How are rotational quantities directly related to linear quantities?

Linking Rotation to Linear Motion

  1. Given the equations in objective 1, calculate w and a .

    clock problems

    fan problems

  2. State the 3 equations that link the linear world to the rotational world.
  3. x = rq

    v = rw

    a = ra

  4. Use the link equations to solve problems.

    linear velocity of a rolling wheel

    wishing well problem

    belt drive problem


Homefun (formative/summative assessment): Read section 8.2, do Section Review Problems 5, 7, 9 p. 200.


Essential Question: How is torque related to a seesaw?


  1. Calculate torque.
  2. t = F x r

    t = F r sinq

  3. Find net torque for various situations with multiple torques.




Homefun (formative/summative assessment): problems 14, 15 p. 203; 16, 17, 18 p. 205


Essential Question: How does the shape of an object and the axis of rotation affect its rotational inertia?

The Moment of Inertia--Rotational Inertia

  1. Define moment of inertia. The resistance to a change in rotational velocity.

  2. State that moment of inertia does not depend on gravity. For example, a sledge hammer will still be hard to swing even in outer space.

  3. Solve problems using the equation for the moment of inertia of a rotating point source of mass. I = m(r^2)

  4. Explain in general terms why different objects with the same mass can have different moments of inertia.

  5. State that an object with the same mass and same diameter but lower moment of inertia will roll down a slope in less time than one with a higher moment of inertia.

  6. Given two or more objects with the same mass, estimate which one will have the highest moment of inertia.

Homefun (formative/summative assessment): problems 21, 22, 23, challenge problem, page 208


Essential Question: How do Newton's laws work for rotation?

Newton's Second Law for Rotational Motion

  1. State Newton's second law for Rotation both in words and mathematically.

    t = I a

  2. Sole problems using Newton's second law for rotation


Homefun (formative/summative assessment): problems 27, 29 page 210


Essential Question: How does center of mass affect a person's balance?

Center of Mass

Relevance: Center of mass is a key issue in sports such as gymnastics, figure skating, and diving. It is a major issue in most forms of martial arts.

  1. Describe how a thrown object will rotate.

  2. Describe how to find the center of mass of an object.

  3. Describe the conditions that cause an object to tip over.

  4. State the differences between stable, unstable and neutral equilibrium.

  5. Describe how forces applied to different locations relative to te center of mass can produce translation and/or rotation.


Essential Question: How can you best prepare for the test?

Review of Objectives 1- 13 (1-3 days)

Formative Assessments:

  1. Work review problems at the board

  2. Work practice problems.

Metacognition Problem Solving Question: Can I still work the problems done in class, several hours or days later? Some amount of repetition on the exact same problems is necessary to lock in learning. It is often better to thoroughly understand a single example of a problem type than to work example after example understanding none of them completely.

Relevance: Good test preparation is essential to performance in physics class.

Homefun (formative/summative assessment): problems 81, 89, 91, 59 pages 193-194; problems turn in on the day stapled to the back of the test.

Summative Assessment: Unit exam objectives 1-23


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