Apologia Physical Science Module 8 Study Guide

Define updraft.

A current of rising air

Define insulator.

A substance that does not conduct electricity very well

Both the Bergeron process and the collision-coalescence process explain precipitation, but they each begin with a different kind of cloud. With what kind of cloud does each theory begin?

The Bergeron process begins with cold clouds, while the collision-coalescence theory begins with warm clouds.

Which of the two theories of precipitation governs the fall of rain from the top of a cumulonimbus cloud? What kind of rain cloud would be most likely described by the collision-coalescence process?

The Bergeron process describes precipitaion from the top of cumulonimbus clouds, while the collision-coalscence theory describes precipitaion from nimbostratus. (Remember, the top of a cumulonimbus cloud is near the top of the troposphere, where water freezes. Nimbostratus clouds, however, are much lower, so they are most likely to be warm.)

What is the difference between drizzle and rain?

Only the size of the raindrop. (Drizzle has very small water droplets, while raindrops are bigger.

What are teh differences between sleet, hail, and freezing rain?

Sleet is much smaller that hail, but both of them are frozen before they hit the ground. Freezing rain, on the other hand, is liquid until it hits a cold surface. (Hail and sleet also form differently, since hail is recycled through the cloud several times while sleet is not.)

A meteorologist measures the dew point on two different mornings. The first morning is very humid and the atmospheric pressure is high. The second morning is not nearly as humid and the atmospheric pressure has fallen. On which day will the dew point be coldest?

The Second morning, (It takes a colder temperature to form dew from air that is less humid or is lower in pressure.)

Name the three stages of a thunderstorm cell in the order they occur. At each stage, , indicate whether an updraft, downdraft or both are present. Also, indicate whether or not precipitation occurs.

1. Cumulonimbus stage - only an updraft, no precipitaion.

2. Mature stage - updrafts, downdrafts, and precipitation.

3. Dissipation stage - only downdrafts and precipitation.

If the heavy rain of a thunderstorm lasts more than 30 minutes, what can you conclude about its makeup?

The thunderstorm is probably made up of several cells. (The mature stage of a typical thunderstorm cell lasts no longer than 30 minutes.)

Lightning forms as a result of electrical charge imbalance. Where does the charge imbalance originate and why does it occur?

The charge imbalance first forms in the cumulonimbus cloud, and it is due to water droplets or ice crystals rubbing against each other in glancing collisions.

Which is responsible for most of the light and sound in a lightning bolt: the stepped ladder or the return stroke?

The return stroke

Where does the thunder in a thunderstorm come from?

Thunder is the result of superheated air traveling out from the lightning bolt in waves. (When those waves hit our eardrum, we interpret them as sound. Since the waves are violent, the sound is loud.)

Why do lightning bolts tend to strike targets that are high?

Lightning strikes tall things because the positive charges in the ground tend to pile up in a tall object, (since that's how they can get closest to the cloud.)

What is the difference between sheet lightning and a lightning bolt?

Sheet lightning is cloud-to-cloud lightning while lightning bolts are cloud-to-ground lightning. (The lightning bolts, therefore, hit the ground, while sheet lightning never does.)

What kind of cloud is necessary for tornado formation?

Cumulonimbus, (The vortex will not form without the strong updraft of a thunderstorm cell that forms a cumulonimbus cloud.)

List the five stages of a tornado in order. At which stage is the tornado most destructive?

1. Whirl stage

2. Organizing stage

3. Mature stage - The tornado ismost destructive in this stage.

4. Shrinking stage

5. Decaying stage

What are the four classifications that lead to a hurricane? What is used to determine which classification a storm fits in?

1. Tropical disturbance

2. Tropical depression

3. Tropical storm

4. Tropical cyclone

The wind speeds in the storm determine in which classification a storm belongs.

What are the conditions in the eye of a hurricane?

Calm and sunny

What causes a hurricane in the Southern Hemisphere to rotate in a different direction than a hurricane in the Northern Hemisphere?

The coriolis effect