What is a brown dwarf?
What will be an ideal response?
A protostar of insufficient mass (less than 8% of the Sun's mass) that does not get hot enough from gravitational contraction to reach 10 million degrees and reach stage 7 as a stable main sequence star.
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In a series RLC circuit an inductor will be dominant at higher frequencies
Indicate whether the statement is true or false
In all living things on Earth, the chemical reactions making, breaking, and combining carbon chains take place in _______________ within the cell of living organisms
Fill in the blank(s) with correct word
Consider a vertical 20-cm-tall flat plate at 120°C suspended in a fluid at 100°C. If the fluid is being forced past the plate from above, estimate the fluid velocity for which natural convection becomes negligible (less than 10%) in: (a) mercury (b) air (c) water.
GIVEN
? A vertical flat plate suspended in a fluid
? Plate temperature (Ts) = 120°C
? Fluid temperature (T?) = 100°C
? Fluid is being forced past the plate from above
? Plate height (H) = 20 cm = 0.2 m
FIND
? The fluid velocity (U?) for which natural convection has a less than 10% effect in
(a) mercury (b) air (c) water
ASSUMPTIONS
? Steady state
SKETCH
PROPERTIES AND CONSTANTS
From Appendix 2, Tables 26, 28 and 13
Emission lines of hydrogen that are found in the ultraviolet part of the electromagnetic spectrum are formed by electrons transitioning from:
A) any level to level 2. B) level 2 to any level. C) any level to level 1. D) level 1 to any level. E) any level to level 3.