The two diagrams describe the main parts of a hot air balloon and indicate how it works. Summarize the information by selecting and reporting the main features and make comparisons with relevant.

The diagram details the various components of a hot

air

balloon

and describes its mechanics. As is evident from the diagram, the three key parts of a hot

air

balloon

are the

envelope

, the

basket

and the

burner

.

In addition

, the hot

air

balloon

’s mechanism for ascending and descending revolves around the thermal regulation of

air

. The main part of a hot

balloon

is a large

envelope

which has an inverted teardrop shape. At the top is the ‘parachute valve’ which is a self-sealing flap used to regulate the pace at which hot

air

escapes. The large vertical sections below the valve are called ‘gores’, which are made up of smaller panels. The

envelope

tapers into a small base called a ‘skirt’. The skirt is attached to the

basket

using ropes, and the

burner

hangs above the

basket

. Inside the

basket

are propane tanks which are used to power the

burner

. Regarding the function of the hot

air

balloon

, the

burner

combines regular

air

with propane to heat the

air

trapped inside the

envelope

, which

then

becomes lighter and

thus

makes the

balloon

buoyant.

To begin

a descent, the

air

is cooled and effectively becomes heavier, pulling the hot

air

balloon

downward.