Props
What is cavitation?
Narrow streams of high energy bubbles that form, compress, and explode as they traverse the blades. This is because pressure on the backside of the blade increases to the point where the water begins to shear.
What does the L represent in model number F150LB?
20″ shaft length
Define Beam.
The greatest width of the boat.
Define current.
A flow of electricity.
What is slip?
Since water is not a solid material, the actual distance the propeller travels will be less than its stated pitch. Slip is referred to as wasted energy and is usually expressed as a percentage of inefficiency.
Current Model Codes use the letter E after the shaft length letter. What does it represent?
Starting Method
Define Freeboard.
The minimum vertical distance from the surface of the water to the gunwale.
Define voltage?
Electric potential expressed in volts.
Define rake.
When viewing the side of a prop, rake (expressed in degrees) is the angle of the blades in relation to the body or barrel of the prop.
The manufacturer date tag is located on the _____ side clamp bracket.
Starboard
Define draft.
The depth of the boat hull under the surface of the water.
Define resistance.
The opposition offered by a body or substance to the passage through it of a steady electric current.
How is a prop diameter measured?
Imagine a circle being formed by the blade tips of a rotating propeller. Next, draw a straight centerline out to the circumference of the the circle and measure that distance.
What is the shaft length for "X"?
25"
Define keel.
The centerline of a boat running from the bow to stern. It is the backbone of the boat.
Define short circuit.
When the load in a circuit has been bypassed and there is no resistance in the circuit.
What is pitch?
Pitch refers to the theoretical distance traveled by a prop as turns one full revolution through a solid.
Identify the engine that uses model code F150TLR
4-stroke; 150hp; 20″ shaft length; ptt/electric start; remote control
What is the "Hole Shot"?
It refers to rapid acceleration of a boat from a standing rest or very slow speed until just on-plane.
Define Ohm's Law.
This law states that the amount of current flowing in a circuit depends upon the amount of voltage in the circuit and the amount of resistance in the circuit.