2 m/s 2.فئرا رؼبعفذ اىق ح صالصخ أ ضبى ب قيذ اىنزيخ ىي ظف فن رن

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1 س\ Physics Dept. Final revision ملخص الوحدة األولى 1.Newton s laws: F = m X a a) An object has a mass of 17 kg and an acceleration of 13 m/s 2. What is the force on the object? 2 جغ مزيز 71 مج رغبسع 71. ف ب اىق ح اى ؤصشح عي زا اىجغ b) Suppose that a sled is accelerating at a rate of 2 m/s 2. If the net force is tripled and the mass is halved, then what is the new acceleration of the sled? افزشع أ ضىجخ رزعجو ث عذه اىعجيخ اىجذ ذح ىي ضىجخ 2 m/s 2.فئرا رؼبعفذ اىق ح صالصخ أ ضبى ب قيذ اىنزيخ ىي ظف فن رن c) A car with a mass of 1000 kg moving with a growing speed and its engine force was 2000 N, find its acceleration. ع بسح مزيز ب 1000 kg رزحشك ثغشعخ زضا ذح مب ذ ق ح اى حشك 2000, N أ جذ اىعجيخ اىز رغ ش ث ب. اجلسم التايل كتلته 5 كجم.احسب عجلته acceleration? d) the object blew has amass of 5 kg,find its e) The block above has an acceleration of 22 ms-2.what is the mass of the block? Choose the correct answer: 1) The sketch shows a block of wood being dragged across a rough horizontal surface at a constant speed by a force F. The magnitude of the frictional force between the block and the surface is ارا ر عحت مزيخ اىخشت عي عطح أفق خش ثق ح F ى زحشك ثغشعخ صبثزخ.فزن ق ح... 1) zero 2)@equal to F 3)less than F 4)greater than F االحزنبك ث اىظخشح اىغطح 2) أ اىحبالد أمجش عجيخ acceleration? In which case will the object have the greatest 1)A 2 )@B 3 )C 4 )D ىزغ ش حشمخ جغ حزبط a.. 3) To change the motion of an object, you need... عشعخvelocity d. مزيخ c. mass ص b. weight ق ح a. force 1

2 3) resultant force acts on a body, which moves from rest in a straight line. Which one of the following graphs shows the relationship between ارا applied? momentum (p) of the object and the time (t) the force is أصشد ق ح حظيخ ىزحش ل جغ عن ف خؾ غزق.فأ األشنبه اىج ب خ ث )م خ اىحشمخ اىض (رعجش ع اىق ح 1 )@A 2 )B 3)C 4 )D أ قب غ قب اىقظ س اىزار inertia? 4) Which of these s the law of a-first. b-second. c-third. d-none of the above. كمية الحركة Momentum: p = mv برا حذس ىن خ اىحشمخ ع ذ ب when: What is happening for momentum رزؼبعف اىنزيخ doubled. 1) Mass is.. ر قض اىنزيخ ىي ظف رضداد اىغشعخ ىيؼعف doubled. 2) Mass is half and velocity is حفظ كمية التحرك conservation: Momentum 1) A cannonball of mass 75 kg was fired at 60 m/s from cannon with mass 300kg, what is the recoil velocity of the cannon? ذفع مزيز 300, kg احغت عشعخ اسرذاد اى ذفع 60 m/s قز فخ ذفع مزيز ب kg75 أ ؽيقذ ثغشعخ 2)The diagram below shows two carts initially at rest on a horizontal frictionless surface being pushed apart when a compressed spring attached to one of the carts is released. اىشنو اىزبى ػح عشثزب رجذآ اىحشمخ عن عي عطح أفق عذ االحزنبك ذفعب جزعذ ثفعو ا ؼغبؽ اىض جشك. if the 1.0 kg cart moves to the left with a speed of 6.0 ms-1, what is the speed of 2 kg cart which moves to the right. اذا تحركت العربة 1.0 kg لليسار بسرعة ms-1 6.0,فما السرعة التي تتحرك بها العربة 2 kg الى اليمين 2

3 3) A 4000kg freight car, moving at 4.0 m/s, collides and couples with a 6000kg freight car, which was initially at rest. ع بسح شح 4000kg رزحشك ثغشعخ 4.0 m/s اططذ ذ اىزظقذ ثغ بسح أخش 6000kg عبم خ احغت اىغشعخ اىجذ ذح ى ب speed. a- Calculate their new combined و اىزظبد ش أ غ ش ش inelastic? a- Is this collision elastic or ب عجت فقذا ؽبقخ اىحشمخ c- Suggest what has happened to the lost kinetic energy Choose the correct answer:- ب اىجغ اىز ى أمجش م خ رحشك momentum? 1. Which object has the greatest a. a 5-kg mass moving at 1 m/sec b. a 75-kg mass moving at 3 m/sec c. a4-kg mass moving at 4 m/sec d. a12-kg mass moving at 1 m/sec 2) A 2.0-kilogram ball traveling north at 4.0 meters per second collides head on with a 1.0-kilogram ball traveling south at 8.0 meters per second. What is the magnitude of the total momentum of the two balls after collision? مشح مزيز ب 2 مج رزحشك ش بال ث عذه 4 زش ىنو صب خ اططذ سأع ثنشح اخش مزيز ب 7 مج رزحشك ج ثب ث عذه 8 زش ىنو صب خ.إحغت ق خ م خ اىزحشك اىني خ ثعذ اىزظبد a)0 kg-m/s b) 32 kg-m/s c) 8.0 kg-m/s d) 16 kg-m/s 3) If an eagle and a bumblebee are both traveling at 10 km/hr, which has the greater momentum? ا ب أمجش ف م خ اىزحشك غش حيخ ى ب فظ اىغشعخ 71 م /ط ال جذ إجبثخ D: neither مي ب C: both اى حيخ B: bumblebee اى غشeagle A: الوزن و الكتلة و الجاذبية Wight, mass and gravity W=mg a) A satellite having a mass of 25 kg experiences a gravitational force of 200. N. Find the acceleration قمر صناعي كتلته 25 كجم يتأثر بقوة جاذبة قدرها 211 نيوتن.إوجد عجلة اجلاذبية يف هذا املوقع location. due to gravity at this b) If your mass was 50 kg, what is your weight in Newton? If g= 10m/s2. Turning effect of Forces 1. Moment العسم =F.d a) In this figure: Calculate the torque ( ). b)the diagram shows a balanced ruler at its center of gravity, what is the length of X. 3

4 ملخص قواويه الوحدة الثاوية 1. Temperature C = ( F - 32), F= 32 + ( C) K= C , C= K Heating and cooling: Q = m c T Specific latent heat: Q = ml 1) Summertime temperatures on Pluto s surface average 45 K the only planet cold enough to keep methane solid. What is this temperature on the Celsius and Fahrenheit scales? ارا ثيغذ دسجخ اىحشاسح ط فب عي عطح م مت ثي ر 45 K فقؾ ث ب نف ىيحفبظ عي اى ضب طيجب. ف ب دسجخ اىحشاسح ث ق بط عيض ط ف ش ب ذ 2) What is the increase in internal energy of 1 kg of water whose temperature goes up 4 o C? The correct specific heat capacity of water is 4200 JKg -1 C -1. احغت م خ اىطبقخ اى نزغجخ ث اعطخ 1 kg اى بء ع ذ ب رشرفع دسجخ حشاسر ث قذاس 4 o C عي ب ثأ اىغعخ اىحشاس خ اى ع خ ىي بء.4200 JKg -1 C -1 3) How many joules of heat are needed to raise the temperature of 10.0 g of aluminum from 22 C to 55 C, if the specific heat of aluminum is 0.90 J/g C? ب عذد اىج الد اىحشاس خ اىالص خ ىشفع دسجخ حشاسح 10.0 g االى 22 C اى 55 C ارا مب ذ اىغعخ اىحشاس خ 0.90? J/g C 4) You have a sample of water with a mass 23.0 g, at a temperature of C. How many kilojoules of heat energy are necessary to carry out each step? Also, calculate the total amount of energy needed to. ارا ثيغذ دسجخ حشاسح مزيخ 23.0 g اى بء C.فبحغت اىحشاسح ة) j k (ىنو خط ح ص احغت اىطبقخ اىني خ اىالص خ تسخين الثلج حتى الصفر C? a. heat the ice to 0.0 انصهار الثلج ice? b. melt the تسخين الماء حتى C? c. heat the water from 0.0 C to غليان الماء water? d. boil the تسخين البخار حتى C? e. heat the steam from C to (C ice = 2000 J/Kg o C, C water = 4200 J/Kg o C, C steam = 2100 J/Kg o C, L f ice = J/Kg, L v water = J/Kg) OR (C for ice = 2.06 J/g oc, C for water = 4.18 J/g oc, C for steam = 2.02 J/g oc, Lf of ice = 334 J/g, Lv of water = 2260 J/g) 4

5 (a) Name the process by which thermal energy is transferred: ب اع اىع ي خ اىز ز ث ب قو اىطبقخ اىحشاس خ : اىش ظ ىألسع Earth, (i) from the Sun to the خاله اى عذ اى ظ ع ا ا اىط pot. (ii) through the metal of a cooking. Choose the correct answer:- 1. Which diagram represents the change in arrangement of the particles in the water as it evaporates? أ األشنبه ظف رغ ش رشر ت جض ئبد اى بء ع ذ رجخش 2. As the temperature of a substance increases, its volume tends to increase due to مي ب صادد دسجخ حشاسح اى بدح فئ حج اى بدح ضداد ثغجت اىز ذد اىحشاس expansion. c.thermal.االرضا اىحشاس a. Thermal equilibrium اىطبقخ اىحشاس خ energy. b.thermal اىز ط و اىحشاس contraction. d.thermal 3. Which of the following is not a widely used temperature scale? أ االر ى ظ قب ظ اىحشاسح اىشبئعخ االعزخذا a. Celsius c. Kelvin b. Joule d. Fahrenheit 4. A substance registers a temperature change from 20 0 C to 40 0 C. To what incremental temperature change does this correspond? ارا ر رغج و رغ ش دسجخ حشاسح بدح 20 0 C اى, 40 0 C فأ رغ ش ف دسجخ اىحشاسح ز افق ع رىل a F c F b F d F 5. Energy is transferred as heat between two objects, one with a temperature of 5 0 C and the other with a temperature of 20 0 C. If two other objects are to have the same amount of energy transferred between them, what might their temperatures be? إرا ا زقيذ اىحشاسح ث جغ أحذ ب حشاسر 5 0 C اىضب 20 0 C.فئرا ا زقيذ فظ م خ اىحشاسح ث جغ أخش ف ب دسجخ حشاسر a C and 15 0 C c C and 32 0 C b C and 25 0 C d C and 90 0 C 6. A slice of bread contains about J of energy. If the specific heat capacity of a person is J/kg.C, by how many degrees Celsius would the temperature of a 70.0 kg person increase if all the energy in the bread were converted to heat? ارا احز د قطعخ خجض عي ؽبقخ 10 J 4.19, اىحشاسح اى ع خ ىشخض ب 10 J/kg.C 4.19.ف ب اىض بدح ف دسجخ حشاسح شخض 70.0 إرا kg رح ىذ ؽبقخ اىخجض اى حشاسح 5

6 a C b C c. d C C م ف ر زقو اىحشاسح اىش ظ اى األسع. Sun? 7. How does heat energy reach the Earth from the a) Radiation b) Conduction c) Convection d) Insulation أ عطح بعت ال عنبط اإلشعبع اىحشاس radiation? 8. Which is the best surface for reflecting heat a) Shiny white b) dull white c) Shiny black d) dull black أ عطح بعت إل زظبص اإلشعبع اىحشاس radiation? 9. Which is the best surface for absorbing heat a) Shiny white b) dull white c) Shiny black d) dull black 10. When Energy is transferred from more energetic to less energetic molecules when neighboring molecules collide this called: ع ذ ب ر زقو اىطبقخ اىجض ئبد األعي ف اىطبقخ إى اىجض ئبد األقو ف اىطبقخع ؽش ق اططذا اىجض ئبد اى جب سح ثعؼ ب اىجعغ, رغ ز اىحبىخ: A) Conduction only اىز ط و B) Convection and radiation اىح و اإلشعبع C) Radiation only اإلشعبع D) Conduction, convection and radiation اىز ط و اىح و اإلشعبع اىظفش اى طيق غب to: 11. Absolute zero equal a) 0 F b) 0 C c) 0 K d) 273 C 12. A solid X is in thermal equilibrium with a solid Y, which is at the same temperature as a third solid Z. The three bodies are of different materials and masses. Which one of the following statements is correct? جغ طيت X زض حشاس ب ع جغ آخش Y اىز ى فظ دسجخ حشاسح جغ صبىش Z, اىضالصخ أجغ خزيفخ ف اىنزيخ اى ع.فأ اىعجبساد ا ر خ طح حخ A capacity. X and Y have the same heat اىجغ ب Yى ب X فظ اىغعخ اىحشاس خ B اىجغ ب Yى ب Z فظ اىطبقخ اىذاخي خ Y and Z have the same internal energy C There is no net transfer of energy if X is placed in thermal contact with Z. ال ر زقو اىطبقخ X اى Z ارا مب ب ف رال ظ حشاس D It is not necessary that Y should be in thermal equilibrium with Z ى ظ اى ج د ارضا حشاس ث. Z Y 12. A molecule of mass m travelling horizontally with velocity u hits a vertical wall at right angles to the wall. It then rebounds horizontally with the same speed. What is its change in momentum? إرا رحشك جغ مزيز m أفق ب ثغشعخ u طذ حبئؾ سأع ثضا خ قبئ خ ص اسرذ أفق ب ث فظ اىغشعخ. ف ب اىزغ ش ف م خ اىزحشك A zero B mu C mu D 2mu 13. Three identical, stationary discs P, Q and R are placed in a line on a horizontal, flat frictionless surface. Disc P is projected head-on towards disc Q. 6

7 ح اىقشصQ P ف خؾ أفق عي عطح عذ االحزنبك.فئرا اططذ سأط اىقشص R, صالس أقشاص ز بصيخ صبثزخQ,P P Q R If the consequent collisions are perfectly elastic, what will be the final motion of the three discs? ارا مب ذ اىزظبد بد ش خ.ف ب اىحشمخ اى بئ خ ىألقشاص اىضالصخ P Q R A ىي غبس Moving Left ىي غبس Moving Left ىي Moving Right B صبثزخ Stationary صبثزخStationary ىيRight Moving C ىي غبسLeft Moving صبثزخStationary ىيRight Moving D ىيRight Moving ىيRight Moving ىيRight Moving أسثعخ أ ع خ زيئخ ث بء عبخ water. Four containers were filled with warm Dull metal Shiny black Shiny metal Dull black i. Which container would have the warmest water after ten minutes? أ األ ع خ حز أعخ بء بء ثعذ 11 دقبئق ى برا Why? ii. The graph below represents changes in a 12kg sample of a substance as it absorbs heat at constant rate from a heater. The specific heat capacity of the substance is 350J/kg O C اىشنو اىزبى ظف رغ ش ع خ 12kg بدح ع ذ ا زظبط ب ؽبقخ حشاس خ.فبرا مب ذ اىغعخ اىحشاس خ ىي بدح 350J/kg O C ب قطخ اىزج ذ substance? a. What is the freezing point of the ب قطخ اىغي ب substance? b. What is the boiling point of the c. What is the minimum energy needed for the substance during the interval AB? ب أقو ؽبقخ حشاس خ ريض خاله اىفزشح AB برا حذس ثبى طقخ BC? d. What happens in the region برا حذس ثبى طقخ EF? e. What happens in the region أعطي سببا : reason Give 1- Alcoholic thermometer can t measure temperature more than 18 C. 7

8 ال ن ىيزش زش اىنح ى ق بط دسجبد حشاسح أعي 18 دسجخ. 2- Mercury thermometer can t measure temperature less than -30 C. ال ن ىيزش زش اىضئجق ق بط دسجبد حشاسح أقو -11 دسجخ. 3- A fire fighting suit is bright and shiny? اىجذىخ اى غزخذ خ قجو سجبه االؽفبء الؽفبء اىحشائق عبدح ب رظ ع اد ال عخ ثشاق 4- In hot countries, people wear bright white clothes and paint their houses white? ف األقطبس اىز ز ض بخ ب ثبىحش فب اى بط شرذ اى الثظ اىخف فخ اىج ؼبء ق ثطالء ث ر ثبىي األث غ 8