Advantage of doorknobs with long handles

  • Thread starter deamonvivid
  • Start date
In summary, torque is defined as the rotational motion of an object and is related to force and the distance from the rotation-axis. This can be demonstrated by the equation rFsin(), where the lever arm is the perpendicular distance from the axis of rotation to the line of action of the force. In terms of decreased force requirements, using doorknobs with long handles instead of standard round ones allows for a decrease in the force needed to apply the same amount of torque. This is because the longer handle creates a larger radius, decreasing the force needed to achieve the same amount of torque.
  • #1
deamonvivid
10
0
Torque question.
What is the advantage of of doorknobs with long handles instead of standard round ones in terms of decreased force requirements?
 
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  • #2
deamonvivid said:
Torque question.
What is the advantage of of doorknobs with long handles instead of standard round ones in terms of decreased force requirements?

What is the definition of torque?
 
  • #3
the rotational motion of an object
 
  • #4
deamonvivid said:
the rotational motion of an object

True.. more specifically, how is that rotational motion caused?

What is the equation for torque?
 
  • #5
deamonvivid said:
the rotational motion of an object

There is a definition of torque that is related to force and the distance from the rotation-axis that the force was applied...
 
  • #6
rFsin()
 
  • #7
the lever arm is the perpendicular distance from the axis of rotation to the line of action of the force
 
  • #8
thats what you talking about right
 
  • #9
deamonvivid said:
rFsin()

yes, exactly... so suppose I apply a certain torque with a certain force F1 at a radius r1... but then I double my r from r1 to 2r1... how much force do I need for the same torque as before (keeping the same angle)...
 
  • #10
deamonvivid said:
thats what you talking about right

yes exactly.
 
  • #11
twice the force as well
 
  • #12
oops, a smaller force
 
  • #13
deamonvivid said:
oops, a smaller force

exactly... only half the force is needed for the same torque...
 
  • #14
deamonvivid said:
oops, a smaller force

Right. Apply this knowledge to your practical usage of doorknobs, the lever one VS. the turning one.
 
  • #15
but i was thinking wasn't the axis of rotation always been considered was at the hinges
 
  • #16
Ok! got it now.
 
  • #17
deamonvivid said:
Ok! got it now.

cool.
 
  • #18
Thanks.
 
  • #19
lol.. real time replying is awesome
 
  • #20
deamonvivid said:
Thanks.

no prob.
 
  • #21
l46kok said:
lol.. real time replying is awesome

lol. yup.
 

1. What is the main advantage of using doorknobs with long handles?

The main advantage of using doorknobs with long handles is that they provide better leverage and grip, making it easier to open and close doors for people of all ages and abilities.

2. Are there any safety benefits to using doorknobs with long handles?

Yes, using doorknobs with long handles can improve safety by reducing strain on the wrist and hand, which can help prevent injuries. They also make it easier for people with disabilities or injuries to navigate through doorways.

3. Can doorknobs with long handles be used on all types of doors?

Yes, doorknobs with long handles can be used on most types of doors, including interior and exterior doors. They are also available in different styles and materials to match the design of any door.

4. Do doorknobs with long handles require any special installation?

No, doorknobs with long handles can be easily installed using the same method as traditional doorknobs. However, it is important to ensure that the doorknob is securely attached to the door to prevent any accidents.

5. Are there any other advantages to using doorknobs with long handles?

In addition to the aforementioned benefits, doorknobs with long handles can also be more convenient for carrying items in and out of a room, as they can be opened with an elbow or hip. They can also add a stylish and modern touch to any door.

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