Question

physics semester 1 review name date per 3. as the temperature of a substance increases, what happens to the average spacing of its molecules? (in general, how is size related to temperature?) 4. what happens to water as it cools from 4°c to 0°c? 5. in all natural processes, the entropy of the universe will do what? 6. explain why, when you jump into a pool just after the first strong cold front of winter, the water is still very warm. general: for each of the following, list the symbol and si units. symbols units (include base units for all derived units) time distance displacement speed velocity acceleration mass force friction weight work energy power momentum impulse centripetal force centripetal acceleration torque heat specific heat latent heat

Explanation:

This problem is about physics concepts (temperature - molecular spacing, water's behavior, entropy, heat capacity of water) and SI units for physical quantities. The subfield under Natural Science is Physics. For the table, we list symbols and SI units (with base units for derived ones):

• Time: Symbol $t$, Unit second ($s$) (base unit)
• Distance: Symbol $d$ (or $s$), Unit meter ($m$) (base unit)
• Displacement: Symbol $\vec{d}$ (or $\vec{x}$), Unit meter ($m$) (base unit)
• Speed: Symbol $v$, Unit $\frac{m}{s}$ (derived, base units $m$ and $s$)
• Velocity: Symbol $\vec{v}$, Unit $\frac{m}{s}$ (derived, base units $m$ and $s$)
• Acceleration: Symbol $\vec{a}$, Unit $\frac{m}{s^2}$ (derived, base units $m$, $s$)
• Mass: Symbol $m$, Unit kilogram ($kg$) (base unit)
• Force: Symbol $\vec{F}$, Unit newton ($N$), $1N = kg\cdot\frac{m}{s^2}$ (derived)
• Friction: Symbol $f$ (or $\vec{f}$), Unit newton ($N$), $kg\cdot\frac{m}{s^2}$
• Weight: Symbol $\vec{W}$, Unit newton ($N$), $kg\cdot\frac{m}{s^2}$
• Work: Symbol $W$, Unit joule ($J$), $1J = kg\cdot\frac{m^2}{s^2}$ (derived)
• Energy: Symbol $E$ (or specific types like $KE$, $PE$), Unit joule ($J$), $kg\cdot\frac{m^2}{s^2}$
• Power: Symbol $P$, Unit watt ($W$), $1W=\frac{J}{s}=kg\cdot\frac{m^2}{s^3}$ (derived)
• Momentum: Symbol $\vec{p}$, Unit $kg\cdot\frac{m}{s}$ (derived)
• Impulse: Symbol $\vec{J}$ (or $I$), Unit $kg\cdot\frac{m}{s}$ (derived, same as momentum)
• Centripetal Force: Symbol $\vec{F}_c$, Unit newton ($N$), $kg\cdot\frac{m}{s^2}$
• Centripetal Acceleration: Symbol $\vec{a}_c$, Unit $\frac{m}{s^2}$ (derived)
• Torque: Symbol $\tau$, Unit newton - meter ($N\cdot m$), $kg\cdot\frac{m^2}{s^2}$ (derived)
• Heat: Symbol $Q$, Unit joule ($J$) (or calorie, but SI is $J$), $kg\cdot\frac{m^2}{s^2}$
• Specific Heat: Symbol $c$, Unit $\frac{J}{kg\cdot K}$ (derived, $J$ is $kg\cdot\frac{m^2}{s^2}$, $K$ is kelvin, base unit related to temperature)
• Latent Heat: Symbol $L$, Unit $\frac{J}{kg}$ (derived)

For the conceptual questions:

1. As temperature increases, molecules gain kinetic energy, move more, so average spacing (volume related) generally increases (thermal expansion, except water below $4^\circ C$).

1. Water expands (becomes less dense) as it cools from $4^\circ C$ to $0^\circ C$ (anomalous expansion of water, due to hydrogen bonding forming a hexagonal structure in ice, taking more space).

1. In all natural processes, the entropy of the universe increases (second law of thermodynamics: $\Delta S_{universe}=\Delta S_{system}+\Delta S_{surroundings}\geq0$, and for natural (irreversible) processes, $\Delta S_{universe}>0$).

1. Water has a high specific heat capacity ($c = 4186\frac{J}{kg\cdot K}$). It takes a lot of energy to change its temperature. The air cools quickly (low specific heat), but the large mass of water in the pool loses heat slowly, so it remains warm initially after a cold front.

Answer:

Conceptual Answers:

1. The average molecular spacing generally increases (thermal expansion, molecules move more with higher KE).
2. Water expands (becomes less dense) (anomalous expansion due to hydrogen bonding in ice formation).
3. The entropy of the universe increases (second law of thermodynamics).
4. Water has a high specific heat capacity; it loses heat slowly, so the pool water remains warm while air cools quickly.

SI Units Table:

Quantity	Symbols	Units (with base units for derived)
Distance	$d$ (or $s$)	meter ($m$, base unit)
Displacement	$\vec{d}$ (or $\vec{x}$)	meter ($m$, base unit)
Speed	$v$	$\frac{m}{s}$ (derived, $m$, $s$)
Velocity	$\vec{v}$	$\frac{m}{s}$ (derived, $m$, $s$)
Acceleration	$\vec{a}$	$\frac{m}{s^2}$ (derived, $m$, $s$)
Mass	$m$	kilogram ($kg$, base unit)
Force	$\vec{F}$	newton ($N$), $kg\cdot\frac{m}{s^2}$ (derived)
Friction	$f$ (or $\vec{f}$)	newton ($N$), $kg\cdot\frac{m}{s^2}$
Weight	$\vec{W}$	newton ($N$), $kg\cdot\frac{m}{s^2}$
Work	$W$	joule ($J$), $kg\cdot\frac{m^2}{s^2}$ (derived)
Energy	$E$ (or $KE$, $PE$)	joule ($J$), $kg\cdot\frac{m^2}{s^2}$
Power	$P$	watt ($W$), $kg\cdot\frac{m^2}{s^3}$ (derived)
Momentum	$\vec{p}$	$kg\cdot\frac{m}{s}$ (derived)
Impulse	$\vec{J}$ (or $I$)	$kg\cdot\frac{m}{s}$ (derived)
Centripetal Force	$\vec{F}_c$	newton ($N$), $kg\cdot\frac{m}{s^2}$
Centripetal Acceleration	$\vec{a}_c$	$\frac{m}{s^2}$ (derived)
Torque	$\tau$	newton - meter ($N\cdot m$), $kg\cdot\frac{m^2}{s^2}$ (derived)
Heat	$Q$	joule ($J$), $kg\cdot\frac{m^2}{s^2}$
Specific Heat	$c$	$\frac{J}{kg\cdot K}$ (derived)
Latent Heat	$L$	$\frac{J}{kg}$ (derived)