Answer:
A river flowing at a certain speed comprises kinetic energy as water has certain velocity and mass
Explanation:
<span>Wrap a magnet in plastic lunch wrap and move it through the mixture of the three solids. The iron filings will stick to the magnet. The filings can be removed by unwrapping the plastic from the magnet carefully! Mix the remaining salt and sand in water and stir.</span>
You can demonstrate that a piece of chalk has mass by putting it on a pan scale. Pan scales determine mass in grams. Also if the mass feels like it has some weight to it (although not to be confused with weight, they are two different things!), it most likely has mass.
Hope this helps!!
Explanation:
Expression for the 
speed is as follows.
where, = root mean square speed
k = Boltzmann constant
T = temperature
M = molecular mass
As the molecular weight of oxygen is 0.031 kg/mol and R = 8.314 J/mol K. Hence, we will calculate the value of as follows.
= 
= 498.5 m/s
Hence, for oxygen atom is 498.5 m/s.
For nitrogen atom, the molecular weight is 0.028 kg/mol. Hence, we will calculate its speed as follows.
= 
= 524.5 m/s
Therefore, speed for nitrogen is 524.5 m/s.
