1. الرحيم الرحمن هللا بسم
البدري عبدهللا الشيخ جامعة
الهندسة كلية
رقم محاضرة(9:)
Work and Energy, Linear and Angular Momentum
والطاقة الشغل,والزاوي الخطي الزخم
Mohammed Abdelgadir Hassan Ibrahim
5. مس خط في جسيم تحرك ثابتة بقوة المنجز الشغلتقيم
Work of a Constant Force Moving Along a
Straight Line.
القوةFcثابتة وبزاوية بقيمة جسيم علي تعمل.
6. الجسيم وزن بواسطة المنجز الشغل:-
Work of a Weight
أعلي الي منحني مسار علي يتحرك جسيم هنالك كان اذا
فقط وزنه بواسطة.
المسار علي اليعتمد المنجز الشغل أن حيث
9. Example(1)
The 10-kg block shown in below Fig. rests on the
smooth incline. If the spring is originally
stretched 0.5 m, determine the total work done
by all the forces acting on the block when a
horizontal force P = 400 N pushes the block up
the plane s = 2 m.
15. Example (2)
For a short time the crane in following Fig. lifts
the 2.50-Mg beam with a force of F = (28 +
3s2) kN. Determine the speed of the beam
when it has risen s = 3 m. Also, how much
time does it take to attain this height starting
from rest?
21. Example(3)
The 50-lb crate shown in below Fig. is acted
upon by a force having a variable magnitude P
= (20t) lb, where t is in seconds. Determine
the crate's velocity 2 s after P has been
applied. The initial velocity is V1 = 3 ft/s down
the plane, and the coefficient of kinetic
friction between the crate and the plane is μk
= 0.3.
29. Example (4)
The 2-kg disk shown in below Fig. rests on a
smooth horizontal surface and is attached to
an elastic cord that has a stiffness kc = 20 N/m
and is initially unstretched. If the disk is given
a velocity (vD )1 = 1.5 m/s, perpendicular to the
cord, determine the rate at which the cord is
being stretched and the speed of the disk at
the instant the cord is stretched 0.2 m.