موضوع مناقشة واجباتPhys101 للترم 122

الواجب الثالث

السؤال الأول ..... B

السؤال الثاني عند t= 6.9 s ..... -3.00

السؤال الثالث

A stone is thrown vertically downward from a building with an initial speed of 3.8 m/s. It reaches the ground after 3.1 s. What is the height of the building? (Give your answer in three significant figures form)

58.9

والله أعلم

 

السؤال الأول
The average speed of a moving object during a given interval of time is always

الاجابة
the distance covered during the time interval divided by the time interval


السؤال الثاني
The coordinate of an object is given as a function of time by x = 7t-3t2, where x is in meters and t is in seconds. Find its average velocity (in m/s) over the interval from t = 0 to t = 2 s. (Give your answer in three significant figures form)

الاجابة
-5.00

السؤال الثالث
A car is allowed to move in the positive x-direction only. The car left position x1 = 3 m at t1= 3 s and reached position x2 at time t2 = 6 s with an average speed of 34 m/s, find x2 (in m). (Give your answer in three significant figures form)

الاجابة
1.05E2 >> معناها 105

 

السؤال الثاني
[FONT=&quot]The coordinate of an object is given as a function of time by x = 7t-3t2, where x is in meters and t is in seconds. Find its average velocity (in m/s) over the interval from t = 0 to t = 3 s. (Give your answer in three significant figures form)[/FONT]

الحل -2.00


السؤال الثالث
[FONT=&quot]A car is allowed to move in the positive x-direction only. The car left position x1 = 3 m at t1= 2 s and reached position x2 at time t2 = 6 s with an average speed of 47 m/s, find x2 (in m). (Give your answer in three significant figures form)[/FONT]

الحل 191

 

نحط الوحدات ولا بس ارقام ؟
وحدات صح هههه

 

بس أرقام

 

هذا الواجب الثاني

طريقة الحل في المرفقات

 

سلام عليكم,,,, هذي حلول HW 2 أن أصبت فمن الله, وان أخطأت من نفسي والشيطان,,,, عالعموم تعليقاتكم!؟

The following five x-coordinate versus time graphs represent the motion of an object along straight line. Which graph represents a motion with constant nonzero speed?

Solution: The graph that has the straight line, means it's speed is Constant.
B

The graph shown below represents the straight-line motion of a car. Find its acceleration at t = 6.7 s. (Give your answer in three significant figures form)

Solution: Use this Formula to solve the question V=Vintial + A T
substitute with A=-9.8,,,,,, then you will have the correct Answer<<<<<
a= -1.79 When Time= 6.75


A stone is thrown vertically downward from a building with an initial speed of 2.9 m/s. It reaches the ground after 2.6 s. What is the height of the building? (Give your answer in three significant figures form)

Solution: Use this Formula Delta X= V Intial T + 1/2 A T^2
Substitute. Then Hight might be in Minus, This because the Stone is going from Origin through the minus y-axis
When you think about it a little bit you will understand that the stone was on hight so the stone must cover a Distance to reach Zero, this mean the Hight must decrease with a Magnitude, To Cover the Distant reaching the Zero Point

Delta X = -25.58 This is for the Above condition V initial=2.9 T=2.6
Remove the Minus only represents the y-axis, there's no Minus actually in Distant
​

 

مع إن الواجب الثاني قفل لكن للفائدة.. القانون المستخدم
في حل السؤال الثاني مثل ما هو موجود في المرفقات..
غلط تاخذ المشتقة لأنه ما طلب منك instantaneous velocity

والله أعلم.

 

Q3 - Assessment 2 :


Velocity = displacement / time

v = x(t2)-x(t1) / t2- t1
v(t2- t1) = x(t2)-x(t1)

x(t2) = v(t2- t1) + x(t1)

Then, just substitute the values and you will get the answer !

 

Solution: Use this Formula to solve the question V=Vintial + A T
substitute with A=-9.8,,,,,, then you will have the correct Answer<<<<<
a= -1.79 When Time= 6.75
ليش؟؟؟؟؟؟؟؟؟؟؟

 

^^

جواب الاخ غلط أصلاً ..

لو تلاحظة من الرسمه في السؤال الثاني طلب when t=6.2 .. ولو تلاحظها وقتها بيكون الـ a كونستنت ! يعني أي قيمة بين الـ 5 و 9 بيعطيك نفس الجواب .. فـ الجواب انك تجيب السلوب .. يعني دلتا v على دلتا t يساوي 12-0 قسمة 5-9 .. الجواب : 3.00- !

 

السـؤال الثالث :

المعطيات :

vi = -3 ( downword (
t=3.1
yi = ??
y = 0

y = yi + vi*t - 1/2 g t^2

وبالتعويض المباشر يطلع لنا الجواب : 56.4

 

السؤال الثاني :
الفكرة ان نحسب الـ التسارع عن طريق حساب الـ slope



الحسابات ارجو التأكد منها

 

الواجب الثالث ..
CH2 - Lec2

السؤال الثاني




طبعا من الثانية ٥ الى ٩ " التسارع ثابت + سالب "



السؤال الثالث

[FONT=&quot]A stone is thrown vertically downward from a building with an initial speed of 4.9 m/s. It reaches the ground after 3.0 s. What is the height of the building? (Give your answer in three significant figures form)[/FONT]


الحل بالمرفقات

او من هذا الرابط
http://store2.up-00.com/Nov12/pmR15260.jpg



​

 

اللي يعرف شي عن السؤال الاول يعلمنا

 

^^

الجواب B : )

كونستانت يعني يكون خط مستقيم , non zero معناتها ان المستقيم يكون مائل

 

معليش السؤال الثاني حصل خطأ في الحسابات

نقدر نحسب الـ slope من النقاط (5,12) و (9,0)

فـ يكون الجواب -3.00

 

B

-3.00

initial speed = 4.7
time = 3.6

Xo=80.4

Remark that the initial speed will be negative because it has been thrown downward