1) What is rotational equilibrium? Clearly describe how you can tell when an object is in rotational equilibrium. Connect to static equilibrium if you can.
An object in rotational equilibrium will rotate with constant angular velocity but may also not be rotating. The sum of an object’s torques adds to 0. An object in rotational equilibrium also has no external torque.
2) What is Torque? How does it relate to rotational equilibrium?
Torque is the tendency of a force to rotate an object. An object in rotational equilibrium has balanced torque forces, likewise an object not in rotational equilibrium has a torque force acting upon it.
3) In what units is it measured? Is this standard world-wide?
The newton-meter is the standard SI unit, whereas foot-pound is common for reference to torque involved in cars.
4) How is it used? What questions does it help us answer?
Torque is used through wrenches, force, levers, and lever/moment arms. Torque can help to measure forces and how big a force is, as well as being used to quantify effects. It helps us answer how much rotational force is being applied to an object on a pivot, door, or lever arm. The amount of rotational force is the torque.
5) How is it similar to force? How is it different?
Torque is similar to force in that it affects the motion and placing of an object. Torque moves objects in a spinning motion, but force moves objects by pushing and pulling, so that is how they are different. When you are spinning an object, you are using Torque to spin it but the forces are pushing and pulling against the top, so that leads us to realize that Torque and Force have a relationship.Torque is different from force because one is linear one is rotational. Force is measured in N and Torque is measured in N*M
6) What does a Free Body Diagram look like for a situation involving Torque?
Free Body Diagrams for situations involving Torque are circular, because of the way torque acts on an object.
An object in rotational equilibrium will rotate with constant angular velocity but may also not be rotating. The sum of an object’s torques adds to 0. An object in rotational equilibrium also has no external torque.
2) What is Torque? How does it relate to rotational equilibrium?
Torque is the tendency of a force to rotate an object. An object in rotational equilibrium has balanced torque forces, likewise an object not in rotational equilibrium has a torque force acting upon it.
3) In what units is it measured? Is this standard world-wide?
The newton-meter is the standard SI unit, whereas foot-pound is common for reference to torque involved in cars.
4) How is it used? What questions does it help us answer?
Torque is used through wrenches, force, levers, and lever/moment arms. Torque can help to measure forces and how big a force is, as well as being used to quantify effects. It helps us answer how much rotational force is being applied to an object on a pivot, door, or lever arm. The amount of rotational force is the torque.
5) How is it similar to force? How is it different?
Torque is similar to force in that it affects the motion and placing of an object. Torque moves objects in a spinning motion, but force moves objects by pushing and pulling, so that is how they are different. When you are spinning an object, you are using Torque to spin it but the forces are pushing and pulling against the top, so that leads us to realize that Torque and Force have a relationship.Torque is different from force because one is linear one is rotational. Force is measured in N and Torque is measured in N*M
6) What does a Free Body Diagram look like for a situation involving Torque?
Free Body Diagrams for situations involving Torque are circular, because of the way torque acts on an object.
Yolo Free Body Diagram
This diagram shows how torque is affecting a yolo (kids toy). The torque is represented on both the left and the right sides of the FBD because torque is not a linear force, it has a rotational presence so it is present on both sides.
7) What new vocabulary is needed to understand Torque?
-8) How is torque calculated? How is it affected by changing the angle of the force?
- Torque = Distance {Moment Arm} multiplied by Force = Distance multiplied by Force multiplied by (Sin(of the angle of the Force))
- T=r x F=r(F)(sin[a])
- Torque is affected by the angle changing because, for example, on a see saw when the legs are moving around the pivot, the torque is changing because the way the object is rotating is changing, and the two are directly related.
Can you explain how to calculate the Torque of an angled force without using a trig function (Using the word "Component")
- To calculate torque you need to take the moment arm and multiply it by Force. In order to find the Force you need to take the radius (arm) and multiply it bythe horizontal force component.
9) What are some examples of Torque in everyday life (this is an important question—include images or pictures)?
- Too see images, please see the real life examples page!
- Hinged Doors are very common examples of force. The opening of a door and its hinges is caused by torque, and the hinges are the pivot point. If you try to open a door by pushing on the door near its hinges, it most likely will not open because there is not enough torque to force it to do so. The length of the moment arm when the door is pushed near the hinges is not large enough to supply enough torque to open the door. In order to open the door, you have to push on the side of the door opposite from the hinges to provide a substantial moment arm which allows for an increased torque to open the door.
- Seesaws are a good example of torque. Many people have had the experience of someone sitting on one end of the seesaw and another person sitting on the other end; and one person is heavier than the other. By sitting closer to the pivot, the heavier person can decrease their torque because the length of the moment arm will be shorter than that of the smaller person. The smaller lever arm results in smaller torque allowing lighter people to lift heavier ones.
- Wrenches also work by torque. (Some wrenches are even calibrated to display the amount of torque the user is applying to a nut; they are called torque wrenches.) The nut (or bolt) is the point of rotation because the user wants to tighten or loosen it by having it turn. The force is being exerted by the hand and arm. People use wrenches to exert a ninety degree force on the nut or bolt. To increase the torque on the nut, either increase the length of the moment arm (length of the wrench) or increase the amount of force being applied to the nut or bolt.
10) What are some examples of simple physics problems that help students grasp the concept of Torque? Show a few solved problems, some with a bit of complexity.
- Torque = Force * Meters, so some physics examples inclue two of those three components and then allow the student to solve for the unknown. We have gotten all of our examples from this linked website. Below are the examples!
- Torque = Distance {Moment Arm} multiplied by Force = Distance multiplied by Force multiplied by (Sin(of the angle of the Force))
- T=r x F=r(F)(sin[a])
- Torque is affected by the angle changing because, for example, on a see saw when the legs are moving around the pivot, the torque is changing because the way the object is rotating is changing, and the two are directly related.
Can you explain how to calculate the Torque of an angled force without using a trig function (Using the word "Component")
- To calculate torque you need to take the moment arm and multiply it by Force. In order to find the Force you need to take the radius (arm) and multiply it bythe horizontal force component.
9) What are some examples of Torque in everyday life (this is an important question—include images or pictures)?
- Too see images, please see the real life examples page!
- Hinged Doors are very common examples of force. The opening of a door and its hinges is caused by torque, and the hinges are the pivot point. If you try to open a door by pushing on the door near its hinges, it most likely will not open because there is not enough torque to force it to do so. The length of the moment arm when the door is pushed near the hinges is not large enough to supply enough torque to open the door. In order to open the door, you have to push on the side of the door opposite from the hinges to provide a substantial moment arm which allows for an increased torque to open the door.
- Seesaws are a good example of torque. Many people have had the experience of someone sitting on one end of the seesaw and another person sitting on the other end; and one person is heavier than the other. By sitting closer to the pivot, the heavier person can decrease their torque because the length of the moment arm will be shorter than that of the smaller person. The smaller lever arm results in smaller torque allowing lighter people to lift heavier ones.
- Wrenches also work by torque. (Some wrenches are even calibrated to display the amount of torque the user is applying to a nut; they are called torque wrenches.) The nut (or bolt) is the point of rotation because the user wants to tighten or loosen it by having it turn. The force is being exerted by the hand and arm. People use wrenches to exert a ninety degree force on the nut or bolt. To increase the torque on the nut, either increase the length of the moment arm (length of the wrench) or increase the amount of force being applied to the nut or bolt.
10) What are some examples of simple physics problems that help students grasp the concept of Torque? Show a few solved problems, some with a bit of complexity.
- Torque = Force * Meters, so some physics examples inclue two of those three components and then allow the student to solve for the unknown. We have gotten all of our examples from this linked website. Below are the examples!
If the same force as in example 1 is applied at an angle of 30 degrees at the end of the 2.0 meter lever, what will be the magnitude of the torque?
Solved:
Sin30 = x/2.0
Sin30 (2.0) = x
1.0 m = x = l
Torque = F * l
Torque = 5.0 N * 1.0 m
Torque = 5.0 N*m
Sin30 = x/2.0
Sin30 (2.0) = x
1.0 m = x = l
Torque = F * l
Torque = 5.0 N * 1.0 m
Torque = 5.0 N*m
A force of 5.0 N is applied at the end of a lever that has a length of 2.0 meters. If the force is applied directly perpendicular to the the lever, as shown in the above diagram, what is the magnitude of the torque acting the lever?
Solved:Torque = F * l
Torque = 5.0 N * 2.0 m
Torque = 10 N*m
Torque = 5.0 N * 2.0 m
Torque = 10 N*m
- As you can see above, both problems are simple algebra that includes plugging numbers into equations.
11) What are some common misconceptions about Torque?
- The most common misconception about torque is that it is the same thing as force, and it is not. Torque is a different concept then force and it effects objects differently then force does. Force is a linear push and pull while torque is a rotational push and pull.
- Other misconceptions are usually relating to the amount of torque applied to something. For example, a car engine with a high torque will actually cause the wheels to rotate at a slower pace rather then a faster pace, the push on the wheel just increases with a high torque therefore making the car move faster.
12) What is center-of-mass? How is it related to Torque?
- The center of mass in an object of system is the point where all of the mass is located. The center of mass is located in the center or middle of an object or surface, and is a place that if there was nothing holding the mass down, the object would be unrestrained in that location.
- Torque revolves around the center of mass in objects that rotate without a pivot. A good example of this is the hoola hoop! The hoola hoop rotates but it does not rotate on a pivot, it rotates around the center of its mass. In that sense, the center of mass is like a balancing point, because the torque must be balanced on that center or else the hoola hoop would fall... which it sometimes does when it becomes unbalanced!
11) What are some common misconceptions about Torque?
- The most common misconception about torque is that it is the same thing as force, and it is not. Torque is a different concept then force and it effects objects differently then force does. Force is a linear push and pull while torque is a rotational push and pull.
- Other misconceptions are usually relating to the amount of torque applied to something. For example, a car engine with a high torque will actually cause the wheels to rotate at a slower pace rather then a faster pace, the push on the wheel just increases with a high torque therefore making the car move faster.
12) What is center-of-mass? How is it related to Torque?
- The center of mass in an object of system is the point where all of the mass is located. The center of mass is located in the center or middle of an object or surface, and is a place that if there was nothing holding the mass down, the object would be unrestrained in that location.
- Torque revolves around the center of mass in objects that rotate without a pivot. A good example of this is the hoola hoop! The hoola hoop rotates but it does not rotate on a pivot, it rotates around the center of its mass. In that sense, the center of mass is like a balancing point, because the torque must be balanced on that center or else the hoola hoop would fall... which it sometimes does when it becomes unbalanced!