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Author Topic: What happens if I reverse the batteries in my toy car?  (Read 11625 times)

Offline DoctorBeaver

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Would it go backwards, not work, or blow up?


 

Offline Chemistry4me

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What happens if I reverse the batteries in my toy car?
« Reply #1 on: 03/07/2009 23:31:34 »
When I tried it, it didn't work.
 

Offline neilep

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What happens if I reverse the batteries in my toy car?
« Reply #2 on: 03/07/2009 23:36:02 »
If it had made it go backwards, what would it have done in a torch?..make anti-light ?
 

Offline DoctorBeaver

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What happens if I reverse the batteries in my toy car?
« Reply #3 on: 04/07/2009 00:23:42 »
Is anti-light the same as dark? If so, how would we tell the difference?
 

Offline Chemistry4me

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What happens if I reverse the batteries in my toy car?
« Reply #4 on: 04/07/2009 00:25:22 »
We probably can't which is why you try it out on your toy car to be absolutely certain!
 

lyner

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What happens if I reverse the batteries in my toy car?
« Reply #5 on: 04/07/2009 01:49:53 »
First, let's ignore the possibility that there may be some electronics in the control circuits that you could blow up.
The motor will change direction if it has a permanent magnet for its  field but will stay in the same direction if the field is produced with an electromagnet because both armature and field swill be reversed.
The difference between the effect on a motor and on a lightbulb is that the motor effect (force) is a vector product of two fields but the power from a lamp is the scalar product of a voltage and current vector - having no sign.
 

Offline neilep

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What happens if I reverse the batteries in my toy car?
« Reply #6 on: 04/07/2009 10:37:28 »
Is anti-light the same as dark? If so, how would we tell the difference?

It would shine out shadows !!
 

Offline Don_1

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What happens if I reverse the batteries in my toy car?
« Reply #7 on: 04/07/2009 14:56:46 »
This is all quite shocking!
 

Offline DoctorBeaver

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What happens if I reverse the batteries in my toy car?
« Reply #8 on: 05/07/2009 22:39:16 »
At least SC replied to this question with appropriate erudition. Thank you, SC. I didn't understand, but thank you anyway.
 

lyner

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What happens if I reverse the batteries in my toy car?
« Reply #9 on: 06/07/2009 15:09:34 »
You remember Fleming's left hand motor rule? The direction of the force depends upon the direction of the current and the direction of the magnetic field. If you reverse them both, the force will stay in the same direction but if you just change one, the force will be reversed.
In a light bulb the only 'force' is a frictionlike force, resisting the motion of the electrons - whichever direction the current flows, the 'force' will always be in opposition.
btw I hesitate in using the word 'force' in that context because it over simplifies things.
 

Offline RD

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What happens if I reverse the batteries in my toy car?
« Reply #10 on: 06/07/2009 21:26:45 »
There is usually "reverse polarity protection" using a diode:
 i.e. nothing happens if batteries are put in the wrong way round.
 Diodes only allow current to flow one way.
« Last Edit: 06/07/2009 21:33:33 by RD »
 

Offline techmind

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What happens if I reverse the batteries in my toy car?
« Reply #11 on: 07/07/2009 21:40:59 »
All small/simple DC motors used in toys that I've ever seen use permanent magnets, so if you reverse the battery then the toy will go backwards.

Of course if the toy contains electronics then (depending on what protection circuits it may or may not have), in the best case nothing will happen and in the worst case you may permanently damage the electronics and it may never work again.

A problem with series protection diodes is that you waste the voltage-drop power. I've seen remote controls which put a high-current diode in reverse-polarity across the battery, so it will short-circuit an incorrectly fitted battery. Whether the diode would survive a reversed battery for more than a few seconds is debateable. The battery might get rather hot and in the extreme even catch fire or explode, especially if they were alkaline/lithium or rechargeable types.
« Last Edit: 07/07/2009 21:44:20 by techmind »
 

Offline pacman77

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What happens if I reverse the batteries in my toy car?
« Reply #12 on: 23/07/2009 06:05:32 »
I have often wondered especially with expensive electronics what would happen if I put the batteries in the wrong way going by this then nothing bad,good to know.
 

lyner

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What happens if I reverse the batteries in my toy car?
« Reply #13 on: 23/07/2009 09:40:19 »
A parallel diode, reversed, won't knacker the battery if you use a fuse.
 

Offline Naufal the B. S.

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Is the bernoulli concept...a
« Reply #14 on: 25/07/2009 02:35:57 »
It'll goes backward...
(If i test it directly to my electric motor)
 

Offline Marc Scott

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What happens if I reverse the batteries in my toy car?
« Reply #15 on: 03/08/2009 12:07:57 »
My brother came home from London for his vacation and gave me a radio-controlled toy car as a present. I have never seen anything like that before! What a speed! And what maneuvering performance! It looks like a real race car and there is a figure of the driver inside. And my brother brought an identical toy car for himself; the only difference is that his is red and a bit smaller in size. We are holding toy car races every day. On the packaging box,  we found the name of the manufacturer  - the company Manuflex Group  and reference to their website newbielink:http://www.manuflexgroup.com [nonactive] maybe, next time he will give me a toy boat from their website for a present?
 

Online Bored chemist

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What happens if I reverse the batteries in my toy car?
« Reply #16 on: 03/08/2009 20:11:27 »
Looks like spam to me.
 

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What happens if I reverse the batteries in my toy car?
« Reply #16 on: 03/08/2009 20:11:27 »

 

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