Answer:
A planetesimal is an object formed from dust, rock, and other materials. The word has its roots in the concept infinitesimal, which indicates an object too small to see or measure. Planetesimals can be anywhere in size from several meters to hundreds of kilometers.
Protoplanets are thought to form out of kilometer-sized planetesimals that gravitationally perturb each other's orbits and collide, gradually coalescing into the dominant planets.
1- mass
2. 3
3. Li2O
4. Of the strong attraction..................
Answer:
68.8 Hz
137.6 Hz, 206.4 Hz
Explanation:
L = Length of tube = 2.5 m
v = Velocity of sound in air = 344 m/s
Distance between nodes is given by

Where n = 0, 1, 2, 3, ...
Making n+1 = n

where n = 1, 2, 3 .....
For fundamental frequency n = 1

Frequency is given by

The fundamental frequency is 68.8 Hz
First overtone

Second overtone

The overtones are 137.6 Hz, 206.4 Hz
If the gears are of different sizes, they can be used to increase the power of a turning force. The smaller wheel turns more quickly but with less force, while the bigger one turns more slowly with more force. Cars and bicycles use gears to achieve amazing speeds our bodies could never match without help.