<span>A fast moving stream of air has a lower air pressure than a
slower air stream. As the stream of air moved over the
top of the paper, the air pressure over the paper dropped. The
air pressure underneath the paper stayed the same. The
greater air pressure underneath lifted the paper strip and it
rose. The idea that a moving air stream has lower air pressure
than air that is not moving is called “Bernoulli’s Principle”.
</span>The
force of the moving air underneath the balloon was enough to
hold it up. The weight added by the paper clip prevents
the balloon from going too high. But that is only part
of the story. The balloon stays inside the moving stream
of air because the pressure inside is the air stream is lower
than the still air around it. As the balloon moves toward the
still air outside of the air stream, the higher pressure of
the still air forces the balloon back into the lower pressure
of the air stream. Bernoulli’s Principle at work again!
Compounds are made of two or more atoms of different elements, such as water (H2O) and methane (CH4). Atoms are not drawn to scale. Molecules of compounds have atoms of two or more different elements.
A catalyst is a substance that increases the rate of a chemical reaction by lowering the activation energy without itself being consumed by the reaction.
Answer:
Mass, m = 1.51 grams
Explanation:
It is given that,
The circumference of Aluminium cylinder, C = 13 mm = 1.3 cm
Length of the cylinder, h = 4.2 cm
We know that the density of the Aluminium is 2.7 g/cm³
Circumference, C = 2πr
Density is equal to mass per unit volume.
m is mass of the cylinder
V is the volume of the cylinder
So,
So, the mass of the cylinder is 1.51 grams.
