Answer:
The van der wall forces are existed between separate molecules of water but not between the hydrogen and oxygen molecules.
Explanation:
<em>Van der wall forces include repulsion and attraction between the atoms, surfaces and molecules.</em> <em>The intermolecular forces are also included in the van der wall forces. Basically, van der wall forces are the forces that are formed between molecules of the same molecules but not with the different molecules of the same substance.</em> Take water molecules into consideration,<em> van der wall forces exist between the water molecules but these forces are not associated between hydrogen and oxygen molecules. </em>These forces are fragile than ionic bond and covalent bond.
The object is in free fall when and only when it is being affected by gravity alone. It is not being influenced by a significant amount of air resistance will always be in free fall. F(net)/m = acceleration
Answer:
Explanation:
To get the person Moving you have to overcome the static (means not moving) friction coefficient. U(static)
To get the person going at the same speed you have to overcome the kinetic friction coefficient. U(Kinetic)
Force to get him moving is 198 N. Force = ma = U(static)Mg
combining the 2 equations you get 198N = U(static)* 55kg *9.8m/s^2 Solve for U(static)
Same equation to keep him moving except with the dynamic force and the dynamic U
175N= U(kinetic)*55kg*9.8m/s^2 Solve (U dynamic)
• Objects “fall” toward the center of Earth. (TRUE)
Since the gravitational force between earth and any object is always along the line joining the centers of two so all the objects near the surface of earth will always feel force towards the centre of the earth due to gravity.
• Objects are pulled by Earth but do not pull on Earth. (FALSE)
Since gravitational force will always follow Newton's III law as per which every action has equal and opposite reaction force so object near the surface of earth will also pull the earth as earth is pulling the object towards the center.
• Objects accelerate at a rate of 9.8 m/s each second. (TRUE)
Since acceleration due to gravity of Earth is 9.8 m/s^2 so here we can say that all objects near the surface of earth will accelerate towards the center of earth at rate of 9.8 m/s^2 due to gravitational pull.
• Objects travel at a rate of 9.8 m/s to are the center of Earth. (FALSE)
Since earth is pulling all objects near its surface with gravitational force so objects can not move at constant speed but it will move with constant acceleration.
• Objects are pulled by Earth more strongly than they pull on Earth. (FALSE)
Since gravitational force will always follow Newton's III law which say every action has equal and opposite reaction so we can say that force due to all objects on earth will be same as the force of earth on the object.
<span>Nitrogen is used to protect steel from water because nitrogen has stable physical properties that enables the nitrogen to be resistant to water molecules. Nitrogen also serves as a coat for the steel to not be corroded easily</span>