from the physics point of view and dealing with static equilibrium...
2007-05-22 17:58:24 · 11 answers · asked by a.n. 1 in Science & Mathematics ➔ Physics
Well, the work you need to do (i.e., the energy spent) would be the same wherever the knob is placed. The work needed is to counter the friction at the hinges (which in turn is mostly due to the weight of the door).
Now, Work = force X distance.
The knob farther from the hinge traces a larger arc (means more distance). Since the work is constant, that means the force needed is reduced. The knob is placed as farther from the hinge as possible so that's it's easier(minimal force required) to move the door.
2007-05-22 19:57:23 · answer #1 · answered by lemmethink 2 · 0⤊ 0⤋
Torque = Force x Lever Arm (length from pivot). The torque is linearly related for a given force to the distance it is applied from the hinge along the perpendicular in the door's plane relative to the rotation axis at the hinge. You put the knob halfway and you need to apply twice the force to perform the same opening task. The knob at the limit of being on the hinge's axis will produce no torque at all.
2007-05-22 19:00:44 · answer #2 · answered by jcsuperstar714 4 · 0⤊ 0⤋
simple try to push open the door near the hinge and then at some distance from the hinge and at the farthest distance from the hinge, you'll find that pushing the door far from the hinge is easier.
this is because, torque = force x distance.
since the torque required to swing open the door is same, either u apply more force at small distance or less force at longer distance.
thats y it is so.
2007-05-22 18:07:08 · answer #3 · answered by rana_22_m 2 · 0⤊ 0⤋
Because, we are treating the door as a lever with the hinge being the fulcrum, and it takes more work (force dot distance) to open or close the door if you do it by the hinges. The longer the distance, the less force needs to be applied.
2007-05-22 18:02:24 · answer #4 · answered by Erich W 2 · 1⤊ 0⤋
TORQUE is what we get by fixing knob away from hinge... thus makin it easy to open the door.......... or it will b too difficult
2007-05-22 18:03:00 · answer #5 · answered by Anonymous · 0⤊ 0⤋
The deadbolt would be too long and the door would be awkward to open.
2007-05-26 09:42:05 · answer #6 · answered by johnandeileen2000 7 · 0⤊ 0⤋
No leverage.
2007-05-22 18:03:53 · answer #7 · answered by BotanyDave 5 · 0⤊ 0⤋
leverage
2007-05-22 18:01:56 · answer #8 · answered by $1200 mistake 3 · 2⤊ 0⤋
Thanks! very valuable information and it offers me better knowledge on this topic
2016-08-20 06:47:05 · answer #9 · answered by Anonymous · 0⤊ 0⤋
I am using this question and answers to show how DUMB Americans are. Thanks.
2007-05-22 18:06:54 · answer #10 · answered by Anonymous · 0⤊ 0⤋