Weight Of Your School Bag. (1 Viewer)

Aplus

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lyounamu said:
Weight = F = ma isn't it?

mass = 10 kg
a = -10

F = -100 newton

Um... it doesn't seem right.

Yes, this is why I didn't choose Physics.
Weight =/= Force. You calculate weight with w = mg, with the g representing acceleration of gravity at 9.8 ms2
 
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lyounamu

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Aplus said:
Weight =/= Force. You calculate weight with w = mg, with the g representing acceleration of gravity at 9.8 ms2
I thought weight was the force.
 

Aplus

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F = ma represents resultant force as far as I know. Weight is always calculated as mg, the straight line force directly from the object to the ground.
 

Nuttaiish

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i am not too sure about the weight of my school bag but it sure does gets heavy with my Hospitality Uniform. Now i wish i have gotten a laptop so much easier.
 

12o9

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Nuttaiish said:
i am not too sure about the weight of my school bag but it sure does gets heavy with my Hospitality Uniform. Now i wish i have gotten a laptop so much easier.
But then you'll have to worry about losing it xD or losing all your work if it crashes =/.
 

Muz4PM

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Aplus said:
Weight =/= Force. You calculate weight with w = mg, with the g representing acceleration of gravity at 9.8 ms2
In physics I thought it did (at least roughly)

You said it yourself, W=mg where g is acceleration of 9.8, so in effect g is a and the equation can be written as W = ma, the same as the force equation.

That is what I thought...
 

Aplus

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Muz4PM said:
In physics I thought it did (at least roughly)

You said it yourself, W=mg where g is acceleration of 9.8, so in effect g is a and the equation can be written as W = ma, the same as the force equation.

That is what I thought...
For F = ma, you use the rate at which the object is accelerating. In W = mg, it's not the rate at which the object is accelerating. It's the constant force of gravitational acceleration towards the object.
 

SimonLee13

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kaz1 said:
You can carry things that are heavier than you. Have you ever heard of Weightlifting?
When you bench, squat etc you are not carrying it. Just lifting temporally. Being able to bench more than your weight does not mean you can carry that weight in a bag...
 

tommykins

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Aplus said:
F = ma represents resultant force as far as I know. Weight is always calculated as mg, the straight line force directly from the object to the ground.
The weight of an object is the force acting on it due to the presence of a graviational field.

lyounamu's right.
 
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Nuttaiish said:
i am not too sure about the weight of my school bag but it sure does gets heavy with my Hospitality Uniform. Now i wish i have gotten a laptop so much easier.
Dang, how much does your uniform weigh?
 

phosphorescent

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God, I hate my bag. It ranges from the weight of a few books to the weight of a dead body.

Okay, a little exaggerated, but sure feels like it.
 

Aplus

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tommykins said:
The weight of an object is the force acting on it due to the presence of a graviational field.

lyounamu's right.
<big>The magnitude of the force of gravity "F" that acts on any object of mass "m" on or near the earth's surface is equal to "mg" where g is the acceleration of gravity:</big>
<big>F = mg</big>.= <big>W</big>
<big>This force is also called the weight (W) of the object.</big>​
 

tommykins

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Aplus said:
<big>The magnitude of the force of gravity "F" that acts on any object of mass "m" on or near the earth's surface is equal to "mg" where g is the acceleration of gravity:</big>
<big>F = mg</big>.= <big>W</big>
<big>This force is also called the weight (W) of the object.</big>​
Go on...f = ma, a happens to be g in the weight that we know.

go on?
 

Aplus

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Acceleration refers to the changing velocity of the object. When we use gravity in calculation of weight, the object is stationary. In any case, both methods are correct, provided you substitute the appropriate figures. I'll stop now.
 
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Doctor Jolly

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Okay the above conversation about physics just threw my physics out of the window .. great :(
 

jasonml

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I reckon my bag weighs about 5kg some days. Which feels like a lot. especially when i'm riding my bike home up the last hill. yaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
 

Wassup?

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My bag weighs about .5 kilos. Seriously, I hold one exercise book, my pencil case, and that's it!
 

BennyTitans

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My Folders the heavy bit my bags pretty light, just a couple of textbooks, food and drink
 

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