A particular lightbulb produces 8 J of thermal energy while producing 2 J of radiant energy, and this is its entire energy output during this time. How energy-efficient is this bulb [as a producer of light]?
A) 400% B) 20% C) 25% D) 500% E) 80%
B
You might also like to view...
Collisions between galaxies are thought to
A) be commonplace. B) have stopped about 5 billion years ago. C) be extremely rare. D) have never occurred. E) have only occurred between 10 and 15 billion years ago.
Three resistors having resistances of 4.0 ?, 6.0 ?, and 10.0 ? are connected in parallel. If the combination is connected in series with an ideal 12-V battery and a 2.0-? resistor, what is the current through the 10.0-? resistor?
A) 0.59 A B) 2.7 A C) 6.4 A D) 11.2 A E) 16 A
All chemical and biological reactions involve the creation and breaking of chemical bonds, which are bonds between the electrons of one atom and the electrons of others
Given this fact, explain why the electromagnetic force governs all chemical and biological reactions. Also explain why the strong force, the weak force, and gravity play no role in these reactions.
A temperature of degrees 260 Celsius is equivalent to _____ Kelvin
a. 8.6 b. 533.2 c. 126.7 d. –13.0