Can anyone help me with these physics questions thanks? (1 Viewer)

[physics123]

<meta http-equiv="Content-Type" content="text/html; charset=utf-8"><meta name="ProgId" content="Word.Document"><meta name="Generator" content="Microsoft Word 11"><meta name="Originator" content="Microsoft Word 11"><link rel="File-List" href="file:///C:%5CDOCUME%7E1%5Creem%5CLOCALS%7E1%5CTemp%5Cmsohtml1%5C02%5Cclip_filelist.xml"><link rel="Edit-Time-Data" href="file:///C:%5CDOCUME%7E1%5Creem%5CLOCALS%7E1%5CTemp%5Cmsohtml1%5C02%5Cclip_editdata.mso"><!--[if !mso]> <style> v\:* {behavior:url(#default#VML);} o\:* {behavior:url(#default#VML);} w\:* {behavior:url(#default#VML);} .shape {behavior:url(#default#VML);} </style> <![endif]--><!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <wunctuationKerning/> <w:ValidateAgainstSchemas/> <w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid> <w:IgnoreMixedContent>false</w:IgnoreMixedContent> <w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText> <w:Compatibility> <w:BreakWrappedTables/> <w:SnapToGridInCell/> <w:WrapTextWithPunct/> <w:UseAsianBreakRules/> <wontGrowAutofit/> </w:Compatibility> <w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel> </w:WordDocument> </xml><![endif]--><!--[if gte mso 9]><xml> <w:LatentStyles DefLockedState="false" LatentStyleCount="156"> </w:LatentStyles> </xml><![endif]--><style> <!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0in; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} span.answerpad {mso-style-name:answerpad;} @page Section1 {size:8.5in 11.0in; margin:1.0in 1.25in 1.0in 1.25in; mso-header-margin:.5in; mso-footer-margin:.5in; mso-paper-source:0;} div.Section1 {page:Section1;} --> </style><!--[if gte mso 10]> <style> /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} </style> <![endif]--> <table class="MsoNormalTable" style="width: 117.54%; margin-left: 6.75pt; margin-right: 6.75pt;" align="left" border="0" cellpadding="0" cellspacing="0" width="100%"> <tbody><tr style=""> <td style="padding: 2.25pt; width: 100%;" width="100%"> A stone is thrown vertically downward from a cliff with a speed of 3.93 m/s. It has 595 J of kinetic energy just before it hits the ground. If the rock had been thrown horizontally instead of vertically, how much kinetic energy would it have just before it hits the ground?

<input name="QUnsaved_0" value="false" type="hidden">
</td> </tr> <tr style="height: 147.15pt;"> <td style="padding: 2.25pt; width: 100%; height: 147.15pt;" width="100%"> A horizontal force of 80 newtons pushes a 50 kilogram object for 8 meters across a level floor. The work done in pushing the object is


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</td> </tr> <tr style=""> <td style="padding: 2.25pt; width: 100%;" width="100%"> A 50 kg crate rests on the floor. The coefficient of static friction is 0.5. The force parallel to the floor needed to move the crate is most nearly:

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</td> </tr> <tr style=""> <td style="padding: 2.25pt; width: 100%;" width="100%"> In the figure below, a block is suspended from two ropes, so that it hangs motionless in the air. If the magnitude of T₂ is 10.0 N, what is the magnitude of T₁?




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</td> </tr> <tr style=""> <td style="padding: 2.25pt; width: 100%;" width="100%"> A force F₁ pushes on an object of mass 10 kg with a force F₂ of 5 N to the right. A force pushes on the same object with a force of 15 N to the left. What is the acceleration of the object?

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</td> </tr> <tr style=""> <td style="padding: 2.25pt; width: 100%;" width="100%"> A bucket of sand of total mass 3.6 kg is suspended from a rope. At a certain instant of time, the tension in the rope is 45 N. What is the net force on the sand bucket at this instant?

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</td> </tr> <tr style=""> <td style="padding: 2.25pt; width: 100%;" width="100%"> What, if any, is the instantaneous acceleration of the sand bucket in the previous question? Give its magnitude and direction.

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</td> </tr> <tr style=""> <td style="padding: 2.25pt; width: 100%;" width="100%"> A 1800-kg car is going down a 8.4 degree incline and applying the brakes. The coefficients of static and kinetic friction between tires and road are μs = 0.80 and
μk = 0.60. The driver is applying the brakes to get the maximum effect without causing the wheels to lock or the tires to skid. Determine the magnitude of the component of the gravitational force on the
car, acting along the incline.

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</td> </tr> <tr style=""> <td style="padding: 2.25pt; width: 100%;" width="100%"> Determine the magnitude of the total friction force of the road on the tires of the car in the previous question.

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</td> </tr> <tr style=""> <td style="padding: 2.25pt; width: 100%;" width="100%"> <o> </o>
</td> </tr> <tr style=""> <td style="padding: 2.25pt; width: 100%;" width="100%"> What is the acceleration of the car on the incline in the previous question?

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</td> </tr> </tbody></table> <o> </o>

 

[townie]

this subforum is for SITE help, i suggest you repost in the physics subsection.

 

[TheStallion]

This sort of stuff is really quite basic, especially the first few questions. You need to study up. I'll give some hints for the first two:

1) KE = 1/2mv^2
2) W = Fs, that is, work = force * displacement.

The rest... the formatting is so bad that I can't even see it properly. Try editing your post and then labelling each question with a number, and make it nice and neat.

 

[Dumbledore]

This sort of stuff is really quite basic, especially the first few questions. You need to study up. I'll give some hints for the first two:

1) KE = 1/2mv^2
2) W = Fs, that is, work = force * displacement.

The rest... the formatting is so bad that I can't even see it properly. Try editing your post and then labelling each question with a number, and make it nice and neat.

i think the first one is more simple, the total initial kinetic energy would be the same had u thrown it up or down, and as u are in the same position on the cliff, the initial gravitational potential energy would also be the same, assuming air resistance is neglected, there will be no loss in mechanical energy so the result would be the same.

 

[Dumbledore]

3. we don't do friction forces in HSC physics, are u sure this isn't part of engineering?
4. can't see diagram

5. bit strangly worded, but it looks like there is 15N of force to the left and 5N to the right so the net force is 10N to the left, F = ma; a = F/m = 10/10 = 1ms^-2

6:i'm not to sure about this one but i'll try:
the tension in the rope is a stretching force which half comes from the force (bucket rope) and half (rope ceiling) so the force from the rope acting on the bucket from the rope is 22.5N. the bucket has a mass of 3.6kg and is subject to by a force of gravity W = mg = 35.28, hence net force is 12.78N downwards. the instantaneos acceleration, F = ma, a = F/m = 12.78/3.6 = 3.55ms^-2

 

[k02033]

""A bucket of sand of total mass 3.6 kg is suspended from a rope. At a certain instant of time, the tension in the rope is 45 N. What is the net force on the sand bucket at this instant?"

the tension pulls the bucket upwards and is greater than the weight of the bucket, so net force is F=45-3.6(9.8), acting upwards.

 

[ilikecheating]

dude you go to la trobe university in melbourne right?


do you own god damn homework, everyone else has to.

i don't think you can go on forums to ask for answers during the final exam so good luck with that.