Science Chapter Review
The capacity to do work is described as
energy
Neither matter nor can be created or but they can be from one to another.
energy destroyed converted form
Everything in the physical universe, left to itself, moves to a state of entropy.
higher
If this were a frictionless plane, what would be the mechanical advantage?
6H/H=6
If the work output for a machine is 450 ft·lb and the work input is 600 ft·lb, what is the efficiency of the machine?
75%
Lightning represents a high discharge of electricity
static
6 CO2 + 12 H2O C6H12O6 + 6 H2O + 6 O2 Check the molecules that represent the source where glucose obtains its carbon.
6CO2
6 CO2 + 12 H2O C6H12O6 + 6 H2O + 6 O2 atoms of carbon are involved in this reaction.
12
How many atoms of hydrogen does alcohol (2C2H6O) have?
12
6 CO2 + 12 H2O C6H12O6 + 6 H2O + 6 O2 hydrogen atoms are involved in this reaction.
24
6 CO2 + 12 H2O C6H12O6 + 6 H2O + 6 O2 molecules of carbon dioxide gas combine with water in photosynthesis.
6
Any energy conversion process ultimately produces
Heat
Potential energy is released whenever an object
Falls
Machines are 100% efficient.
False
When high velocity water strikes turbine blades is converted to
Kentic Energy mechanical energy
Heat is energy
True
The lowest temperature possible is:
absolute zero
Which devices may overtax a community's electric power?
air conditioners
Why must both sides of a chemical equation balance?
all of the above
If matter cannot be created or destroyed within the physical universe, then the total quantity must be
constant
The transfer mechanism of heat through gases and liquids by circulating currents is called
convection
The resistance of moving surfaces produces
friction
What happens to the density of nearly all objects as they cool down?
it increases
Atomic energy is stored within the of an atom.
nucleus
To find the mechanical advantage of any machine, take the force and divide by the force
output input
An atom which loses an electron becomes charged.
positively
