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Sample Practice Test Questions
What does the timing belt do?
synchronizes the camshaft and the crankshaft
Maintaining proper synchronization between the rotation of the camshaft and the rotation of the crankshaft is critical to ensure that the engine's valves open and close at the proper times during each cylinder's intake and exhaust strokes.
During continental drift, the drifting plates move across which of the following?
liquid mantle
The crust and the rigid lithosphere (upper mantle) is made up of approximately thirty separate plates. These plates more very slowly on the slightly more liquid mantle (asthenosphere) beneath them. This movement has resulted in continental drift which is the gradual movement of land masses across Earth's surface. Continental drift is a very slow process, occurring over hundreds of millions of years.
The intake ports on the cylinder heads is fed outside air via the:
intake manifold
The intake manifold distributes outside air to the intake ports on the cylinder heads. The intake air filter removes any airborne contaminants before the air enters the engine.
A dominant trait will be expressed when paired with:
a recessive trait
The traits represented by genes are inherited independently of each other (one from the male and one from the female gamete) and a trait can be dominant or recessive. A dominant trait will be expressed when paired with a recessive trait while two copies of a recessive trait (one from each parent) must be present for the recessive trait to be expressed.
What type of current flows in only one direction in a circuit?
direct
Direct current flows in only one direction in a circuit, from the negative terminal of the voltage source to the positive. A common source of direct current (DC) is a battery.
Which of these will have the most impact on the kinetic energy of an object?
its speed
Kinetic energy is the energy of movement and is a function of the mass of an object and its speed: \(KE = {1 \over 2}mv^2\) where m is mass in kilograms, v is speed in meters per second, and KE is in joules. The most impactful quantity to kinetic energy is velocity as an increase in mass increases KE linearly while an increase in speed increases KE exponentially.
Which of these is not necessary for combustion?
accelerant
Combustion is the burning of an air-fuel mixture to provide energy. It requires the presence of air, fuel, and a heat source to ignite the air-fuel mixture. In the internal combustion engine that powers automobiles and trucks the combustion happens inside the engine utilzing a fuel like gasoline, diesel fuel, or natural gas.
Which of the following is not true about a line drop?
it is addressed by raising current and lowering voltage across the ransmission line
Electricity is delivered from power stations to customers as AC because it provides a more efficient way to transport electricity over long distances. A line drop is a decrease in voltage between two points on an electrical transmission line due to resistance in the line. A lower current and higher voltage across the line will help compensate for the line drop.