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PHYSICS Resultant of Forces 1, Whalis the magnitude of the resultant force of the two forces 200 N at 20° and 400 N at 144°? .932.5N B.323.5N C.313.5N D. 233.5 N 2. The magnitude of the resultant of the following system of coplanar concurrent forces: 5N, 30°; 10N, 140°; 8N,220° is rs }0.2N B.11N C.11.5N D. 12.6N Forces in Equilibrium 3. A load of 100 Ib is hung from the middle of a rope, which is stretched between two rigid walls 30 ft apart. Due to the load, the rope sags 4 feat in the middle. Determina the tension on the rope, A. 165 Ibs B. 173 Ibs (C194 Ibs D. 149 Ibs 4. A 20 ft ladder ts teaning on the wall, Half-way on the ladder is a 150 Ib mass. Find the reaction on the upper end of the ladder, if the distance of its lower ond is 8 ft fram the wall fn 73 tb B, 28.40 Ib C, 24,21 Ib D. 20,80 Ib 5. A50-kg steel pipe 4.0 m tong Is supported by a rope attached 1.7 m from one end. The downward force that must be applied to the e! ot the pipe closest to the rope to keep the pipe horizontal is ABBN . 86 N C,227N D. 490 N Friction 6. The coefficient of static friction of steel on ice is 0.1. The force needed in newtons to set a 70 kg skater in motion is about 407 B7 ()10 D. 700 7. A 250 Ib block is initially at rest on a flat surface that is inclinéd at 30°. If the coefficient of kinetic friction is 0.30 and the coefficient of static friction is 0.40, find the, to start the block moving up the plane. A. 190 Ib C 212Ib NAG Hist D. 75 Ib 8. A6 m ladder weighs 350 N fid is placed with its I rand on a horizontal floor and its upper end against a wall. The angle between the wall and the ladder is 30°. A man weighing 900 N is to climb to the very top of the ladder. The coefficient of friction between the wall and the ladder is 0.20. What must be the minimum coefficient of friction between the floor rie ladder to avoid the danger of slipping? ). 0.420 A.0.322 B. 0.403 0.488 D. Work, Energy & Power 9. A 100-kg carwhose speed is 80 knv/h has a kinetic energy of A.252E4d B.247E5U C.2.42E6J D.3.20E6J 10. A force of 200 Ibf acts on a block at an angle of 28° with respect to horizontal. The block is pushed 2 feet horizontally. What is the work done by this force? A.215J B.320J C.480 3 D. 5405 11. An automobile has a power output of 1HP. When it pulls irt with a force of 300 N, what is the cart's velocity? A.0.249 m/s B. 249 mis C. 24.9 ms C) 2.49m/s 12. A power of 6 kW is supplied to the motor of a crane. The motor has an efficienc; 90%. With what constant speed does the crane lift an 800 Ibf weight? A.0.09 m/s B.0.32 m/s C. 0.98 m/s D. ¥.52 mis Momentum Problems Ff birex ind > Path ends Wut Males CVI wor muggtinn velouthy ayes BEN obte 13. Two cars having equal weights of 135 kN are travelling on a straight horizontal track with velocities of 3 mds to the right and 1.5 m/s to the left respectively. They collide and are coupled during impact. Neglecting friction due to sliding, determine their final common velocity. (A/0.75 mis B. 1.2 mis C.0.56 mis (hs ms 14. A baif'rolling to the right on a level table at 2.5 m/s strikes head-on an identical ball\hatis at rest. Find a) C. 2.5 ms moving to the right . 2.5 m/s moving to the left D. 1.2 ms moving to the right 15. A100 kg body moves to the right at 5 m/s and another body of mass W moves to the left at 3 m/s. They meet each other and after impact the 100 kg body rebounds to the left at 2 m/s. Determine the mass of the other body if coefficient of restitution is 0.5. the ise of the first ball after collision. Assume a perfectly elastic collision. a A. 100 kg B.120 kg C. 130 kg D. 180 kg 16. A40 g bullet is fired with a velocity of 500 mis ata sta 40 kg body. it exits with a velocity of 200 mis. The velocity of the block after being hit is A05ms 8.0.9 mis CA2 ms D.1.5 m/s 17. A 5-g bullet with a muzzle velocity of 300 m/s strikes a 1-Kg block hanging vertically in a 1-m rope. If the bullet is imbedded in the block, calculate the height reached by the block. A.0.058 m (apt m C. 0.302 m D.0.375 m Page 1 of 4 Laie wladhy 
