ASVAB: Mechanical Comprehension Questions and Answers With Complete Solutions

The wheel of a car has a diameter of 16 inches and moves a smaller wheel of 4 inches. What is the mechanical advantage gained by the system? a.)1:4 b.)4:1 c.)1:2 d.)2:1 - ✔✔b.)4:1 A lever a.)Reduces resistance b. ...

The wheel of a car has a diameter of 16 inches and moves a smaller wheel of 4 inches. What is the mechanical advantage gained by the system? a.)1:4 b.)4:1 c.)1:2 d.)2:1 - ✔✔b.)4:1 A lever a.)Reduces resistance b.)Multiplies force and changes direction c.)Transmits power from one object to another d.)Cannot move in the reverse direction - ✔✔b.)Multiplies force and changes direction Tension can best be called a.)A weight b.)A force c.)A movement d.)A direction - ✔✔b.)A forceWhich of the following wedges generates the greatest amount of force. a.)11" long and 4" high b.)9" long and 4" high c.)7" long and 4" high d.)5" long and 4" high - ✔✔a.)11" long and 4" high You're trying to replace a flat. How much torque are you applying to a wheel nut if you're applying 40 pounds with a wrench measuring 9"? a.)4 ft-lb b.)30 ft-lb c.)53 ft-lb d.)360 ft-lb - ✔✔*Torque is calculated by multiplying force (in pounds) and length (in feet). Thus, 40 pounds multiplied by .75 feet gives us 30 ft-lb of torque. 1 ft=12 in Divide 9 in by 12 ft=.75ft b.)30 ft-lb Which of the following situations requires overcoming the least amount of kinetic friction? a.)Pushing an empty refrigerator box down a path b.)Pushing a refrigerator in its box down a path c.)Pushing an empty refrigerator box down an icy path d.)Pushing a refrigerator in its box down an icy path - ✔✔c.)Pushing an empty refrigerator box down an icy pathWhat measures how much force is applied to an object in order to rotate it? a.)Torque b.)Friction c.)Pressure d.)Vector - ✔✔a.)Torque Which of the following is NOT a unit of power? a.)Watt b.)Horsepower c.)Volt-ampere d.)Newton - ✔✔d.)Newton What is the potential energy of a 4 lb. book held 50 feet in the air? a.)1,960 J b.)268 J c.)200 J d.)27 J - ✔✔*Potential energy is calculated by multiplying mass (in kilograms), acceleration due to gravity, and height (in meters). Thus, the potential energy of the book is 268.128 J: 1.8 kilograms multiplied by 15.2 meters multiplied by 9.8 m/s2. b.)268 JWhen a machine compounds the force you use, it gives you a(n) a.)Mechanical advantage b.)Output advantage c.)Mechanical leverage d.)Output leverage - ✔✔a.)Mechanical advantage Which of the following is an example of potential energy? a.)Rain falling b.)A bowling ball rolling c.)A slinky at the top of stairs d.)A person walking down a hill - ✔✔c.)A slinky at the top of stairs *Potential energy is energy that can be converted to movement, like a diver ABOUT to jump. Potential energy is dependent on an object's position. For example, a diver at the top of a tall cliff has considerable potential energy. Potential energy is measured in joules (J). A 180 pound person dives off of a 30 foot cliff. What is their velocity as they enter the water? a.)588 m/s b.)178 m/s c.)24 m/s d.)13 m/s - ✔✔d.)13 m/s *x = (vi)*t + (1/2)*a*t^230 = (0)*t + (1/2)*(32)*t^2 30 = 16*t^2 30/16 = t^2 t^2 = 1.875 t = sqrt(1.875) t = 1.369306 vf = vi + a*t vf = 0 + 32*1.369306 vf = 43.817792 feet per second that converts to 13.3556630016 m/s so the answer is choice D A perfectly efficient machine a.)Uses the least amount of horsepower b.)Provides the biggest mechanical advantage c.)Converts all the power applied to it into outputted force d.)Provides the simplest route to accomplish the task - ✔✔c.)Converts all the power applied to it into outputted force *A machine that is 100% efficient converts all of the power applied to it into output force. This is highly unlikely due to wear and tear, friction, and general imperfections.What is the point at which the lever pivots? a.)The force point b.)The shaft c.)The fulcrum d.)The axle - ✔✔c.)The fulcrum *the point on which a lever rests or is supported and on which it pivots. What is energy stored in chemicals or released in a chemical reaction? a.)electrical b.)potential c.)chemical d.)kinect - ✔✔c.)chemical A machine made up of two or more simple machine working together. What kind of machine is this? a.)equilibrium b.)compound c.)mechanical d.)fulcrum - ✔✔b.)compound A force that pushes materials together.a.)effort b.)compression c.)resistance d.)compound - ✔✔b.)compression In a lever, the point where you apply force. a.)flexibility b.)effort c.)friction d.)kinetic - ✔✔b.)effort In a lever, the distance from the force to the fulcrum. a.)effort arm b.)load arm c.)tension d.)potential - ✔✔a.)effort arm Energy in moving electrons a.)potential energy b.)electrical energy c.)resistance d.)effort force - ✔✔b.)electrical energyThe ability of a material to bend without breaking. a.)effort force b.)flexibility c.)potential d.)resistance - ✔✔b.)flexibility The force that resists the relative motion of two surfaces in contact. a.)effort force b.)friction c.)gravity d.)load - ✔✔b.)friction An attractive force between objects a.)effort force b.)resistance arm c.)power d.)gravity - ✔✔d.)gravity Simple machines are useful in that they a.)Simplify tasks b.)Create a mechanical shortcutc.)Are easy to design and build d.)Reduce the effort needed to accomplish a task - ✔✔d.)Reduce the effort needed to accomplish a task Work occurs when a.)Force is applied b.)Force is applied in a certain direction c.)Force is unable to overcome resistance d.)Force is used to move something over a distance - ✔✔d.)Force is used to move something over a distance *Work occurs when force is used to move something, overcoming resistance, over a certain distance. Work results in movement, otherwise, it is just force. Work is calculated by multiplying force by distance. The formula is W=Fd. Work is measured in joules, force is measured in newtons, and distance is measured in meters. 15 J of work were expended moving an 18 kg block. At what velocity did the block move? a.)1.3 m/s b.)1.1 m/s c.).9 m/s d.).7 m/s - ✔✔a.)1.3 m/s *To solve for velocity, you should use the formula W = KE, where Work = W, and Kinetic Energy = KE. This is because any work that is done to accelerate an object is converted to thekinetic energy of that object (the work-energy theorem). So, W = (1/2) mv2. Plugging in the block's weight (18 kg) and the work done (15 J) will give you a velocity of 1.3 m/s. Energy is a.)The power of motion b.)The application of force c.)The capacity to do work d.)The opposition of weight - ✔✔c.)The capacity to do work *Energy is the capacity to do work: to change something. The measure of the quantity of matter in an object is its a.)Mass b.)Force c.)Weight d.)Density - ✔✔a.)Mass