I have a doubt in this Physics question.

[Yewheng]

In line w the New A n O level direction of setting morally correct n environmentally correct questions w view of senstivity to animals n living objects, such questions have already been phased out of A level/ O level GCE papers.

 

WHO in e right mind wld think of dropping a mouse n elephant? Who wld be able to drop an elephant w/o much effort in e first place? Ridiculous n stupid assumptions in e first place.

 

The wood n styrofoam qtn wld be of a better quality as it involves much more achievable assumptions. However do bear in mind that the relationship between surface area, velocity of object dropping, viscoscity of the fluid in which the object is travelling all contributes to the retardation force due to air resistance and this force is always trying to slow down the object n hence the object will reach terminal velocity needing longer time. The equation to solve this problem is not as straight forwards as retardation force F is proportional to kvsq (for high velocity object) or kv (for low velocity object). Those who did Mechanical engineering @ Uni level will know that u need a modelling equation which involve at least a 2nd order differential equation to solve real life simulation.

 

Oh so am I right to say lower air pressure will result in object drop at faster rate than higher air pressure? So a object drop at let's say 3000m as compared to the same object drop at 50m.. the object drop at 3000m will fall at faster rate.. (correct?)

 

And in other space ( vaccum ) object can float because there is no mangatic force pulling object downwards.. as in earth itself has magnatic force.. thus a compass can show which heading is south and which heading is north.. hmm..

Edited July 17, 2011 by Yewheng

[Leeke1]

Pls help me. When a mouse and an elephant are dropped from the same height. Which animal will reach the ground first? Why?

elephant will touch the ground 1st....coz of the size of the elephant and both going down at the same acceleration.

[Leeke1]

imagine the elephant is 1 meter away from the ground...but the mouse is 5 meters away from the ground...both droping from the same height....of coz the elephant will hit 1st....this is not physics la...is IQ...haha

[Gendut]

Oh so am I right to say lower air pressure will result in object drop at faster rate than higher air pressure? So a object drop at let's say 3000m as compared to the same object drop at 50m.. the object drop at 3000m will fall at faster rate.. (correct?)

 

And in other space ( vaccum ) object can float because there is no mangatic force pulling object downwards.. as in earth itself has magnatic force.. thus a compass can show which heading is south and which heading is north.. hmm..

 

And in other space ( vaccum ) object can float because there is no mangatic not enough gravitational force pulling object downwards

[Sabretan]

And in other space ( vaccum ) object can float because there is no mangatic not enough gravitational force pulling object downwards

 

 

technically, the phrase not enough gravitational force is not correct. Rather it is a balance of gravitational forces acting on the object in space that creates this balance situation. Two planets/stars exert a gravitational force on the object n assuming the object to be a point with respect to the size of the planets n stars so that we can assume the contribution of grativitational force of attraction from this object is neglible, will attract the object w gravitational forces of attraction determined by Newton's law of gravitational attraction forumula. Thus if the forces acting on this object are equal but opposite, this object will carry on travelling in its original velocity or carry on remaining stationary.

 

But u r right in the sense that it is gravitational force that pulls the object.

[Yewheng]

And in other space ( vaccum ) object can float because there is no mangatic not enough gravitational force pulling object downwards

 

Oh ok thanks.. I learn something.. [rolleyes]

[Sabretan]

Oh so am I right to say lower air pressure will result in object drop at faster rate than higher air pressure? So a object drop at let's say 3000m as compared to the same object drop at 50m.. the object drop at 3000m will fall at faster rate.. (correct?)

 

And in other space ( vaccum ) object can float because there is no mangatic force pulling object downwards.. as in earth itself has magnatic force.. thus a compass can show which heading is south and which heading is north.. hmm..

 

 

Not a straightforward answer as u might have hope. It depends on the air pressure difference. more specifically, the air pressure difference rate of change or gradient.

 

 

However, if we make the following assumptions that u r taking abt say Earth Atmoshpere, and dropping an identical object under the same condition except for air pressure difference, I am sorry to tell u that the object dropped at 50 m will reach the ground first.

[Happily1986]

so is air resistance a function of only surface area and not mass at all?

 

function of velocity as well and the functional relationship changes with the range of speeds

[Gendut]

technically, the phrase not enough gravitational force is not correct. Rather it is a balance of gravitational forces acting on the object in space that creates this balance situation. Two planets/stars exert a gravitational force on the object n assuming the object to be a point with respect to the size of the planets n stars so that we can assume the contribution of grativitational force of attraction from this object is neglible, will attract the object w gravitational forces of attraction determined by Newton's law of gravitational attraction forumula. Thus if the forces acting on this object are equal but opposite, this object will carry on travelling in its original velocity or carry on remaining stationary.

 

But u r right in the sense that it is gravitational force that pulls the object.

 

That was what i exactly meant to say. But would it not be just easier saying gravity not enough?

 

Minister say teach less learn more but I never believe ministers anyway.

Edited July 18, 2011 by Gendut

[Subutai]

I say Elephant.

 

Because it is trying to get away from the mouse by jerking, twisting, kicking and diving in the air. [grin]

[Moredhel]

Pls help me. When a mouse and an elephant are dropped from the same height. Which animal will reach the ground first? Why?

 

Ans: "The answer is subjective for the reason that a factor in deriving a logical answer is missing from the equation. I take it that the tester means to test my skills of assumption and I shall answer to the best of my ability. Assuming the ground is flat and measureable distances remains constant for the purpose of this testing, then:

 

Option 1: The mouse was dropped at 12 noon and the elephant was dropped at 12 midnight on the same day. The mouse would reach the ground first.

 

Option 2: The elephant was dropped at breakfast and the mouse was dropped at dinnertime. The elephant would reach the ground first.

 

Option 3: Both the elephant and mouse were dropped at the same time. Taking into account geothermal, genetic modifications, neo-gravity and negative mass factors, assuming the weather was fair with light headwinds and minimal turbulence, the likelyhood of the mouse reaching the ground first is 86.754615692%. While active calculations are able to prove such, the actual formulas would require a piece of paper about the size of 30 football fields, which is quite impossible to realize on this small space provided. If you are a young, hot tester in your early twenties with a figure men would die for and a face men would describe as 'CFM', kindly contact me at the number written on the back of this paper for a more in-depth examination of the formulas including addition, subtraction, division and multiplication, not necessarily in that order. Should you be anything else other than the described, please proceed to the shortened answer provided below.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The reason for this is explained simply. We know that mighty mouse can both fly and land fast, but dumbo mostly only knows how to fly.

[The_Bear]

How come no one asked about the morality of dropping innocent animal from height? Was any animals harmed in the testing of this theory?

[Subutai]

How come no one asked about the morality of dropping innocent animal from height? Was any animals harmed in the testing of this theory?

 

MOE fault.

[VellfireS]

How come no one asked about the morality of dropping innocent animal from height? Was any animals harmed in the testing of this theory?

knn.. HAHA.. I like your point of view there.. [laugh]

[1fast1]

How come no one asked about the morality of dropping innocent animal from height? Was any animals harmed in the testing of this theory?

 

Erwin Schr

[Sabretan]

How come no one asked about the morality of dropping innocent animal from height? Was any animals harmed in the testing of this theory?

 

 

sensitivity of this issue w regards to cruelty towards animals had been stated earlier. which is why such qtns are phased out of A/O level exams. Only some insensitive sch under MOE still used such qtns, not to mention tuition center as well.

[Sabretan]

That was what i exactly meant to say. But would it not be just easier saying gravity not enough?

 

Minister say teach less learn more but I never believe ministers anyway.

 

 

I think Gravity more than enuf...Rather it is money not enuf.

 

The greatest joke of this era is Teach less learn more...I say teach less lose more...as in u teach less, expect students to learn more on their own, u will lose more of them in trying to finish the syllabus.

 

Go n ask ur sons, daughters, nephews, nieces, etc if they like their school imposed self-directed learning, elearning etc??

 

 

but then, it is the brain child of some scholars...

[Subutai]

I think Gravity more than enuf...Rather it is money not enuf.

 

The greatest joke of this era is Teach less learn more...I say teach less lose more...as in u teach less, expect students to learn more on their own, u will lose more of them in trying to finish the syllabus.

 

Go n ask ur sons, daughters, nephews, nieces, etc if they like their school imposed self-directed learning, elearning etc??

 

 

but then, it is the brain child of some scholars...

 

Brain child of scholars? More like making our offspring stupid so that theirs are smarter and thus maintaining / ensuring their elite status.