Work and Energy    (1)   If a man lifts a 20-kg bucket from a well and does 6 kJ of work, how deep is the well?  Assume the speed of the bucket remains constant as it is lifted. من معطيات هذا السؤال نجد أن الشغل المبذول = 6000J ووزن الجسم 200N والمطلوب إيجاد عمق البئر […]

Mechanics: Kinematics Description of Motion    (1)   An athlete swims the length of a 50-m pool in 20 s and makes the return trip to the starting position in 22 s. Determine his average velocity in (a) the first half of the swim, (b) the second half of the swim, and (c) the round trip.

Introduction: Physics and Measurements [1] Show that the expression x=vt+1/2at2 is dimensionally correct, where x is a coordinate and has units of length, v is velocity, a is acceleration, and t is time.   نقوم بإيجاد وحدة الطرف الأيمن ونساويها بوحدة الطرف الأيسر من المعادلة وفي حالة تساوي الأبعاد (الوحدات) لطرفي المعادلة فإن المعادلة تكون

(1) What potential difference is needed to stop an electron with an initial speed of 4.2×105m/s? حيث ان الشعل يساوي التغير في طاقة الحركة W = Δk = kf-ki W = 0-ki qV = -1/2 mv2 V = -(1/2 mv2)/q V = -(1/2 x 9.1×10-31x(4.2×105)2)/1.5×10-19 V = -0.57 volt (2) An ion accelerated through a

(1) An electric field of intensity 3.5´103N/C is applied the x-axis.  Calculate the electric flux through a rectangular plane 0.35m wide and 0.70m long if (a) the plane is parallel to the yz plane, (b) the plane is parallel to the xy plane, and (c) the plane contains the y axis and its normal makes

(1) The electric force on a point charge of 4.0mC at some point is 6.9´10-4N in the positive x direction.  What is the value of the electric field at that point? من معطيات المسألة (القوة الكهربية الموؤثرة على شحنة في الفراغ) يمكن حساب المجال الكهربي عند تلك النقطة من خلال التعريف الاساسي للمجال وهو حاصل