soto soto (ags2658) HW 4: Forces (Statics) gill (201202) 1

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1 soto soto (ags2658) HW 4: Forces (Statics) gill (201202) 1 This print-out should have 30 questions. Multiple-choice questions may continue on the next column or page find all choices before answering. 001 (part 1 of 4) 0 points A ladder leans against a wall while someone climbs up, as shown in the figure below. 002 (part 2 of 4) 0 points Which way does the force point at position B? l B d W l W p A Which way does the force point at position A? None of these s 8. None of these 003 (part 3 of 4) 0 points Considerthecasewhereboththewallandthe floor are rough. Which way does the force due to point at position A? 8.

2 soto soto (ags2658) HW 4: Forces (Statics) gill (201202) 2 M 8. None of these The following figures show several attempts at drawing free body diagrams for the sphere. Which figure has the correct directions for each force? The magnitudes of the forces are not necessarily drawn to scale. 004 (part 4 of 4) 0 points Whichwaydoestheforceduetopoint at position B? None of these graphs are correct. Since the sphere is not moving, no forces act on it (part 1 of 2) 0 points A spherical mass rests upon two wedges, as seen in the figure. The sphere and the wedges are at rest and remain at rest. There is no between the sphere and the wedges.

3 soto soto (ags2658) HW 4: Forces (Statics) gill (201202) (part 2 of 2) 0 points The wedges themselves lie on a horizontal table. There is between the table and the wedges. The following figures show several attempts at drawing free body diagrams for the left wedge. Which figure has the correct directions for each force? The magnitudes of the forces are not necessarily drawn to scale. Since the sphere is not moving, no forces act on it points

4 soto soto (ags2658) HW 4: Forces (Statics) gill (201202) 4 Atoycarisgivenaquickpushsothatitmoves up an inclined ramp. After it is released, it moves up, reaches its highest point and moves back down again. Friction is so small it can be ignored. What net force acts on the car? Net constant force down the ramp Net increasing force down the ramp Net decreasing force down the ramp Net constant force up the ramp Net decreasing force up the ramp Net force of zero Net increasing force up the ramp points Consider a buggy being pulled by a horse. Which is correct? The force on the buggy is as strong as the force on the horse. The horse is joined to the Earth by flat hoofs, while the buggy is free to roll on its round wheels. Thehorsepullsbeforethebuggyhastime to react so they move forward. Thehorsecanpullthebuggyforwardonly if the horse weighs more than the buggy. The horse pulls forward slightly harder than the buggy pulls backward on the horse, so they move forward. 009 (part 1 of 3) 0 points A 47 N object is in free fall. What is the magnitude of the net force which acts on the object? 010 (part 2 of 3) 0 points What is the magnitude of the net force when the object encounters 17 N of air resistance? 011 (part 3 of 3) 0 points Whatisthemagnitudeofthenetforcewhenit falls fast enough to encounter an air resistance of 47 N? 012 (part 1 of 2) 0 points Sue and Jenny kick a soccer ball at exactly the same time. Sue s foot exerts a force of 51 N to the north. Jenny s foot exerts a force of 107 N to the east. a) What is the magnitude of the resultant force on the ball? 013 (part 2 of 2) 0 points b) What is the direction of the resultant force (measured from East)? Answer in units of points Beth, a construction worker, attempts to pull a stake out of the ground by pulling on a rope that is attached to the stake. The rope makes an angle of 67 with the horizontal. If Beth exerts a force of 146 N on the rope, what is the magnitude of the upward component of the force acting on the stake? points Two men decide to use their cars to pull a truck stuck in mud. They attach ropes and one pulls with a force of 617 N at an angle of 25 with respect to the direction in which the truck is headed, while the other car pulls with a force of 1067 N at an angle of 16 with respect to the same direction.

5 soto soto (ags2658) HW 4: Forces (Statics) gill (201202) N N What is the net forward force exerted on the truck in the direction it is headed? points A staging that weighs W staging supports a painter weighing 350 N. The reading on the leftscaleis600nandthereading ontheright scale is 240 N. 019 (part 2 of 2) 0 points What force is exerted on the sled by the hill? 020 (part 1 of 2) 0 points Consider a 686 N cat burglar supported by a cable as in the figure N 240 N Find the tension in the inclined cable. What is the of the staging? points A 70kg block is inequilibrium on anincline of 39. The acceleration of gravity is 81 m/s 2. What is F n of the incline on the block? 018 (part 1 of 2) 0 points A child holds a sled on a less, snowcovered hill, inclined at an angle of N F 31 If the sled weighs 56 N, find the force exerted on the rope by the child. 021 (part 2 of 2) 0 points Find the tension in the horizontal cable. 022 (part 1 of 2) 0 points The 6 N is in equilibrium under the influence of the three forces acting on it. The F forceactsfromaboveontheleftatanangle of α with the horizontal. The 1 N force acts fromaboveontherightatanangleof55 with the horizontal. The force 6 N acts straight down. α F 1 N 6 N 55 What is the magnitude of the force F? 023 (part 2 of 2) 0 points What is the angle α of the force F as shown in the figure?

6 soto soto (ags2658) HW 4: Forces (Statics) gill (201202) 6 Answer in units of points Consider the 116 N light fixture supported as in the figure. The right-hand cable had tension 390 N and makes an angle of 43 with the ceiling. The right-hand cable makes an angle of 43 with the ceiling and has a tension of 390 N T2 θ N 615 N Find the tension in the supporting wires. 025 (part 1 of 2) 0 points Consider the 667 N held by two cables shown below. The left-hand cable had tension 890 N and makes an angle of θ with the wall. The right-hand cable had tension 960 N and makes an angle of θ 1 with the ceiling. a) What is the tension T 2 in the left-hand cable slanted at an angle of θ 2 with respect to the wall? 028 (part 2 of 2) 0 points b) What is the angle θ 2 which the left-hand cable makes with respect to the ceiling? Answer in units of. 890 N θ 1 θ 667 N 960 N 029 (part 1 of 2) 0 points Consider the 637 N held by two cables shown below. The left-hand cable had tension T 2 and makes an angle of 55 with the ceiling. The right-hand cable had tension T 1 and makes an angle of 36 with the ceiling. a) What is the angle θ 1 which the righthand cable makes with respect to the ceiling? Round up to four significant digits. Express unit as degrees. Answer in units of degrees. T T (part 2 of 2) 0 points b) What is the angle θ which the left-hand cable makes with respect to the wall? Round up to four significant digits. Express unit as degrees. Answer in units of degrees. 027 (part 1 of 2) 0 points Consider the 615 N held by two cables shown below. The left-hand cable had tension T 2 and makes an angle of θ 2 with the ceiling. 637 N a) What is the tension in the cable labeled T 1 slanted at an angle of 36? 030 (part 2 of 2) 0 points a) What is the tension in the cable labeled T 2 slanted at an angle of 55?