Mechanic Exam A+ Correctly solved, Exams of Mechanics

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Mechanic Exam A+ Correctly solved

E= - ANSWER IR

P= - ANSWER IE

Pie r^2 = - ANSWER Area of a circle 231 in^3 / - ANSWER gal. 25.4mm/ - ANSWER in. 2.2kg/ - ANSWER lb 3 phase rectifier output = - ANSWER 1.33 x input single phase output = - ANSWER 0.9 x input RMS (effective voltage) = - ANSWER 0. (PEAK V) TC = - ANSWER R x C (5)??? RPM = - ANSWER 60 (frequency) / (poles/2) door overlap minimum = -

Platform Lift Sill to " - ANSWER 3/8" to Gibs minimum = - ANSWER 1/4" min Gate Switch maximum = - ANSWER 2" Passenger Sill to Sill to " - ANSWER 1/ 1-1/2" Moving Walk maximum = - ANSWER 12 degree max Governors (Car Trip Speed = & Overspeed Switch = ) - ANSWER Car trip speed 15-20% greater than contract speed. Overspeed Switch less than or equal to 90-95% of trip speed CWT ( %) - ANSWER Up to 10% greater than car trip speed

1. A contractor wants to raise the car speed from 100FPM to 125FPM. It currently has a 12" sheave. What size sheave is required? - ANSWER 15"

----Diam = 12, 12"/4=3, 25FPM=3in : 100FPM + 25FPM = 12"+3" =15"

7. You need to work on a freight door retiring cam. You LOTO the mainline disconnect, but there is still power to the cam. What circuit is still hot? - ANSWER Mainline disconnect. (535) (3.2.6)
8. The contractor requests that the vertical center of the rack and pinion hoist be moved. How is this accomplished? - ANSWER Adjust tie downs/ wall ties (850).
9. Working pressure on a Hydro is a 400 psi. What is the correct relief valve setting? - ANSWER 600 psi max. (805), 400psi x 150% = 600psi 10)What must first be installed on a false car before operation? - ANSWER Safeties (110) note: handrails & buffers also required 11)There is a slight arcing at the brush and commutator. What actions must be taken? - ANSWER None. (430) Note: Heavy arcing due to light brush pressure, mechanical wear indicates heavy brush pressure. 12)If rigging gear is roped 3:1 and a beam clamp is used to lift a 6000 lb load. What is the beam capacity requirement? - ANSWER 18000 lb. (210).

note: When

being 4 times the diameter of the

rope from the top of shackle max and the second 8 times the diameter of the rope from the first. 19)A 300ohm resistor burns out. You don't have a 300ohm resistor. What can you use to make up the resistor? - ANSWER TWO 600ohm resistors in parallel, (600) the resistance is the half of the highest rating in a parallel circuit. As is THREE 225ohm resistorsin parallel equal 75ohms. 20)When cutting laminated panels, which direction should the finished side face? - ANSWER Finished face of the material should face the cutting edge of the tool (255). The blade has a tendency to burr the back side. 21)A 480 vac step down 240 vac transformer is connected to a 3 phase rectifier. What will be the output? - ANSWER 320 vdc 22)How do you cut a finished floor material? - ANSWER Cutting blade away from the finish (255) 23)Car is loaded with 125% and sinks. Why? - ANSWER Slipped through the brake 24)If you find a broken or missing barricade, what do you do? - ANSWER Write up a formal inspection request.

30)A car weighs 2500 lbs with a capacity of 2500 lbs, the CWT is weighted at 40%. How much is the motor lifting at 100% load? - ANSWER 1500 lbs. 2500x40%= 1000 lbs 2500+1000 = 3500 5000-3500 = 1500 lbs 31)How must oxygen and acetylene tanks be stored? - ANSWER Must be stored vertically 12 ft apart, or on a cart w/ a 1/2 hr fire rated barrier between them 32)What does the code state about sill to sill distance? - ANSWER 3/4" to 1 1/2" spacing 33)If the sill to sill distance is 1 3/4". What will bring it into code spec? - ANSWER -.5" 34)When drilling a jack hole in sandy conditions what type of drill rig is required? - ANSWER Rotary or Auger bit (805) NOTE: Rotary - compacted soil, percussion - rocky conditions, and percussion rotary - solid rock 35)A customer does not want an escape hatch on his residential elevator. Under what conditions is this legal? - ANSWER Manual operation must be

provided (850)

43)You perform a static load test with the pit valve in the closed position. The car sinks 6" in 15 min. What is the cause? - ANSWER Cylinder leak (520) 44)Where should you point a fire extinguisher when putting out a fire? - ANSWER at the base of the fire. 45)A car with a selective collective controller is moving to the lobby to pick up a call. An up call is put in at the second floor. What happens? - ANSWER Call is bypasse til the car is moving in the up direction. 46)During construction you land an escalator, but it is 10mm too low. What is wrong? - ANSWER Pit is too deep or column mark is off (825) 47)During construction the omega CWT rails have been damaged. Why? - ANSWER Overtightened from rail to bracket (215) 48)How do you handle a coworker who shows up to work intoxicated? - ANSWER Speak to the MIC (Foreman), union BA, or call your supervisor 49)How do you attach brackets to brick? -

ANSWER Inserts 1/4" back from brick

o R2 A R GRD 55)There is voltage at the switch but none at point A. What is wrong? - ANSWER Either open R1 or R2 (635) 56)What does the square with a darkened upper triangle represent? USE PRINT 730 TO SOLVE - ANSWER DC Relay NOTE: Square with lower triangle = latching relay, and square with arrow through it = timer 57)The close door limit switch is not working. You have power from Term 35 to Term 8, no power from Term 1 to S2. Why? - ANSWER Door limit switch malfunction 58)Car is running normally but the buzzer will not shut off. Why? - ANSWER EHP 3 to 2 shorted 59)Relay STR has voltage, TRU has voltage, RU has no voltage. Why? - ANSWER TRU 11 9/ 60)2nd floor PI illuminates then quickly extinguishes. Why? - ANSWER XI 4 and 6

61)Car will not travel to 2nd floor without a 3rd floor call, and will not go down from 3rd without a 2nd floor call. What is the problem? - ANSWER 2FI4/ 62)Using print #3, why wont the motor start? - ANSWER MOL 1 T/B 63)The step level switch on an escalator has been activated. Where do you check? - ANSWER Both top and bottom (825). Step switches are manual reset switches. They are activated if the step drops 1/4" or more. 64)You get a trouble call for in-op freight door. What must you do first before you begin work? - ANSWER Block the door open 65)You get shocked when you attempt to move a car using a temp button for the first time. Why? - ANSWER You forgot to hook up a ground wire (810) 66)A motor needs a sleeve bearing replaced. What type of bearing will you need? - ANSWER Friction bearing (420)