It must have a medium. It must travel in empty space. Mechanical waves are waves which needs medium of propogation.
Answer:
1⁺ ion
Explanation:
Metals in the first group on the periodic table will prefer to form 1⁺ ion. This is because the 1 valence electron in their orbital.
Most metals are electropositive and would prefer to lose electrons than to gain it.
Like all metals, the group 1 elements called the alkali metals would prefer to lose and electron.
On losing an electron the number of protons is then greater than the number of electrons. This leaves a net positive charge.
Answer:
The value is 
Explanation:
From the question we are told that
The molar mass of hydrazine is 
The initial temperature is 
The final temperature is 
The specific heat capacity is ![c_h = 0.099 [kJ/(mol K)] = 0.099 *10^3 J/(mol/K)](https://tex.z-dn.net/?f=c_h%20%20%3D%20%200.099%20%5BkJ%2F%28mol%20K%29%5D%20%3D%200.099%20%2A10%5E3%20J%2F%28mol%2FK%29)
The power available is 
The mass of the fuel is 
Generally the number of moles of hydrazine present is

=> 
=> 
Generally the quantity of heat energy needed is mathematically represented as
=>
=>
Generally the time taken is mathematically represented as

=> 
=> t = 2480505.6377 s
Converting to hours

=> 
Ok well I know measure of long leg is 30 degrees and short leg is 60 degrees
Answer:
0.853 m/s
Explanation:
Total energy stored in the spring = Total kinetic energy of the masses.
1/2ke² = 1/2m'v².................... Equation 1
Where k = spring constant of the spring, e = extension, m' = total mass, v = speed of the masses.
make v the subject of the equation,
v = e[√(k/m')].................... Equation 2
Given: e = 39 cm = 0.39 m, m' = 0.4+0.4 = 0.8 kg, k = 1.75 N/cm = 175 N/m.
Substitute into equation 2
v = 0.39[√(1.75/0.8)
v = 0.39[2.1875]
v = 0.853 m/s
Hence the speed of each mass = 0.853 m/s