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[align=right]السسسسلام عليكم و الرحمة
أحتاج الى مساعدتكم في بضعة اسئلة احتاجها لاختبارٍ بعد يومان لذلك اريدها بأسرع وقت جزاكم الله خير الجزاء
اما المجموعة الثانيه من الاسئلة فهي لاختبار الاسبوع القادم[/align][align=left]
المجموعة الاولى:
Vector A=-4i+3j
Vector B=2i+5j-k
Find:
1-Angle of vector A with respect to x-axis
2- Angle of vector B with respect to z-axis
3- Vector C which is perpendicular to vector A and lies in the third quadrant and its magnitude equals 5
4- The direction of vector C
5- Vector D which is perpendicular to both vectors A and B
3-Direction of vector D with respect to x-axis



المجموعة الثانيه:
A rock is thrown directly upward from the edge of the roof of a building that is 54.7 meters tall. The rock misses the building on its way down, and is observed to strike the ground 4.00 seconds after being thrown. Take the acceleration due to gravity to have magnitude 9.80 m\s^2 and neglect any effects of air resistance. With what speed was the rock thrown?



A ball is projected upward at time t = 0.0 s, from a point on a roof 70 m above the ground. The ball rises, then falls and strikes the ground. The initial velocity of the ball is 31.9 m/s. Consider all quantities as positive in the upward direction. The time when the ball strikes the ground is ?



A ball is projected upward at time t = 0.0 s, from a point on a roof 80 m above the ground. The ball rises, then falls and strikes the ground. The initial velocity of the ball is 56.7 m/s. Consider all quantities as positive in the upward direction. At time t = 2.9 s, the acceleration of the ball is ?



An airplane undergoes the following displacements: First, it flies 66 km in a direction 30ْ east of north. Next, it flies 49 km due south. Finally, it flies 100 km 30ْ north of west. Using analytical methods, determine how far the airplane ends up from its starting point[/align]

جزاكم الله الف خير