Mechanical engineer Interview Questions
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Mechanical Engineer interview questions shared by candidates
If given four projects of equal importance with the same due date, what would you do. Be specific
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just some more info while we all wait(i know this process is painful- ive been through it a few times without good luck, unfortunately) June 13th is the tentative start date for ALL examiners for this round of hiring so that should tell you a lot. i just heard this today and apparently the Supervisors are apparently suppose to turn in their lists by tomorrow so calls/emails obviously follow after that is done. We might hear something later since the start date would be further down the road. i'll keep updating if i find out more or hear back from them. btw, the chemicals and computers i think hear back first and the electrical and mechanicals may hear back later as their interviews were conducted in that order. Less
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I applied for EE position and just received notification that I have been selected. Last name starts with "C" and interviewed on April 13th. It seems that the selections for EE and Comp Science will begin to be sent today. It may take until Friday for HR to finish sending all decisions to the applicants. Best of luck to everyone and very grateful to all who have contributed to this posting. Less
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I interviewed on 4/13 for a BME position and received notification on 5/2 that I was selected. In a follow up email for the Declaration of Federal Employment form, they indicated a tentative start date of 6/13. Hope this info is helpful for those still waiting - good luck! Less
If two vehicles are identical, except for one weighing twice as much as the other vehicle, and they roll down a hill, which car reaches the bottom first? Neglect air resistance. Assume the extra mass is in the body of the vehicle.
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The heavier car reaches the bottom first because the rotating inertia (wheels) of that car makes up a smaller percentage of of its mass. This is why the question mention /where/ the extra mass of the heavier car is. Less
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They reach at the same time. Assuming the mass is included in the body and minimal friction and no air resistance, mass will not be a factor. PE will be completely transformed to KE by the bottom of hill meaning mgh=.5mv^2, mass cancels out meaning mass doesn't matter. This is similar to dropping a feather and a bowling ball on the moon. No air resistance so they hit the ground at same time. Don't over think it. That's the worst thing you can do in an interview. Less
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Same time... Don't listen to the rest of the shmos what we are really worried about here are the cars acceleration From FDB: F = ma = mgcos(theta) - FrictionForce = mgcos(theta) - mu*NormalForce = mgcos(theta) - mu*mgsin(theta) Divide both sides by m, and there is no mass left in equation... just a = gcos(theta) - mu*gsin(theta) Therefore, the equation is independent of mass and they arrive at the same time. Less
If you were in a dark closet with 49 white socks and 1 black one.how many socks would you pick so as to ensure that you exit the closet with a pair of similar colored socks
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3 socks
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All of them. In a dark closet it is hard to distinguish colors.
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At least 3
Whats your experience?
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just explain your experience based on your summary.
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ingin berkerja di pertamina
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yes i'm want join to pertamina
need to join tomorrow are you ready?
13 Answers
If you have a refrigerator in an isolated room (no heat in or out) and left the door to the refrigerator open, what would happen to the temperature to the room? Would it go up, down or say the same?
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The refrigerator will warm up the room. If you look on the back of the refrigerator, you will see metal grating. Touch it. Its warm! A refrigerator is transporting heat from the inside cavity to the outside. However, the power cord running from the wall is pumping energy into the refrigerator/room. Energy is powering the refrigerator. It is also running an irreversible process, the energy dissipates out as heat and work (mostly heat), making the net temperature of the room increase. Less
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In this case, there is a net gain of energy from the refrigerator outlet into the room and no loss of energy out of the room. Thus, the room will warm up since there is a gain of energy. Less
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The temperature and overall heat content of the room will increase. Yes, the fridge it providing cooling, but it is doing this by removing heat from part of the air and dumping it into other parts of the air, all while doing work which is harnessed from the power input (electricity) from the wall. In other words, the heat in the air is just displaced from one area of air to another, so no loss nor gain of net heat, HOWEVER the work used to do this creates additional heat. If you consider this from a total energy standpoint, all energy within the room is fixed, except there's energy being added through the power input, so there's an increase in energy with time. I'm shocked at some of the other answers here, I hope those saying the temperature remains the same do not have mechanical engineering degrees. Less
in a boat on a lake with a rock, throw the rock in the water which way does the water level move? here is a memory card- what is it made out of and how was it made?
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the water level goes down. Think about an extreme case. You have an small item made of the worlds most dense material in the hull of the boat. Even though the volume of the item is small the weight is very heavy. This pulls the boat down and since the volume that the boat displaces will be much higher then that of the small item, when the item is thrown over board, the boat lifts further out of the water displacing less water causing the level to decrease. Less
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no change in water level. it will be the same as it was when the rock was on the boat. Less
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Archimedes Principal. Weight of rock is displacing water upwards when in the boat. When in the water it is displacing its volume. Water has to go down since the density of most rocks > water Less
What are your goal for the next 5 years and how do yo plan to achieve them?
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I have one innovation and I really want to show that all world as soon as possible Less
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I was retired during 5 years
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I have 43 years experience in general mecanical and pipeline from I was 12 years old Less
You're in a row boat, which is in a large tank filled with water. You have an anchor on board, which you throw overboard. Does the water level in the tank rise or fall?
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Actually I feel the water level won't change. Since, the anchor is thrown from the boat there are two situations. a. Before being thrown : The anchor is in the boat and it's weight is accounted by the volume submerged. b. After being thrown: The anchor is now transferred from the boat to the tank. So even though the water level increases, the volume of the boat submerged, decreases. In essence one balances the other and there shouldn't be any change in the water level. Less
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When an object is submerged in water , the lift/buoyant force on it is equal to the weight of water displaced. Case 1 Mw1*g = (Mb +Ma)*g ; Mw = dw*(A*h1) h1 = (Mb+Ma)/(dw) Case 2 , Boat is floating and anchor is completely submerged. h2 = (Mb)/(dw) +Ma/(d_steel) , where d_steel is density of steel > density of water (dw) clearly h2 < h1 , so the water level falls Less
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Two possibilities Water displaced is proportional to buoyancy = weight supported 1. The anchor is attached to the boat and does not reach bottom Total buoyancy = boat + anchor which doesn't change before or after -> no change in water level 2. The anchor rests on the bottom of the lake Total buoyancy after water level lowered Less
You put a glass of water on a record turntable and begin slowly increasing the speed. What happens first - does the glass slide off, tip over, or does the water splash out.
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I was asked this question in separate interviews by Apple, then later by Lab126 (Amazon). I got the answer correct, and they told me so. This question evaluates candidates intuitive sense (engineering judgment) about how things behave when subject to multiple forces, including visualizing free body diagrams and understanding how multiple forces can be resolved into resultant forces (and their angles) to predict how a body moves. The conceptual answer is: this problem can be understood by considering a sufficiently small fluid element at the surface of the water in the glass. That tiny sub-volume of water experiences two forces: 1) gravitational force pulling down on that small mass of water; 2) the force of centripetal acceleration acting upon that small mass of water. When viewed in the (rotating) reference frame of that tiny volume of water under study, the centripetal force is a side-acting force and the gravitational is downward acting. The surface of the water will change to a shape that is NORMAL to the resultant vector of those two forces. Holding rotational freq constant, the water angle will get steeper as its radial location on the record player increases, because the centripetal force is proportional to radius multiplied by the SQUARE of the angular frequency. It can be shown that the water will take on the shape of a sub-portion of the surface of a PARABOLA centered with its minima at the center axis of the record player. As the angular frequency increases, the glass will either slide, or it will tip over, and which of these depends on the aspect ratio of the glass (position of COG) and the friction between the glass and the record player. Some water could splash out prior to either of those events, if the glass was nearly filled with water before the water angle started to change when the turntable started spinning Downward acting gravitational force: F = m X g Side acting centripetal force: F= (omega^2) X r, where omega is angular freq in rad/s If THETA = the tangential angle of the water relative to the plane of the record player, then: TAN (Theta) = (omega^2) r / g Interviewers often give major credit if candidate can at least get CONCEPTUAL answer correct. Less
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Depends on several factors including where the glass is placed (the outer edge will experience stronger forces) and how much water is in the glass (I think). Less
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The above description is largely correct except this "It can be shown that the water will take on the shape of a sub-portion of the surface of a PARABOLA centered with its minima at the center axis of the record player." This is true only if the glass is placed at the center of the record player..in all other cases the shape will not be the same due to the effect of centripetal force acting on just direction (as opposed to uniform/all direction in the case of rotating glass at the center) Less