Your Results | Global Average | |
---|---|---|
Questions | 5 | 5 |
Correct | 0 | 3.58 |
Score | 0% | 72% |
Work is measured in:
watts |
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joules or newton-meters |
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amps |
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horsepower |
Work is performed on an object when an applied force causes displacement along the same vector. Measured in joules (J) or newton-meters (Nm), work is calculated by multiplying force times displacement: \(W = \vec{F}\vec{d}\)
Which of the following is not a base unit in the metric system?
liter |
|
meter |
|
gram |
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degree Fahrenheit |
The Fahrenheit scale is used for measuring temperature in the British system. The metric system uses the Celsius scale.
Which of the following is not a method of heat transfer?
radiation |
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conduction |
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reflection |
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convection |
Heat is always transferred from warmer to cooler environments through conduction, convection, or radiation.
Materials like metals that transfer heat efficiently are called:
reflectors |
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conductors |
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refractors |
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insulators |
Heat is always transferred from warmer to cooler environments and conduction is the simplest way this transfer can occur. It is accomplished through direct contact between materials and materials like metals that transfer heat efficiently are called conductors while those that conduct heat poorly, such as plastic, are called insulators.
Which of the following substances gives up negatively charged hydroxide ions (OH-) when dissolved in water?
hydrogen |
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ion |
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acid |
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base |
An acid is a substance that gives up positively charged hydrogen ions (H+) when dissolved in water. A base (alkaline) gives up negatively charged hydroxide ions (OH-) when dissolved in water. pH is a scale that measures of how basic or acidic a solution is. Numbered from 0 to 14, solutions with a pH of 7 are neutral, less than 7 are acidic, more than 7 are alkaline.