Q 24: Newton's first law of motion states that anything that stands still will stay still unless unbalanced force is acted upon that object. Newton's second law of motion states that the velocity of an object changes when subjected to external Force. Newton's third law of motion says that for every action there is an equal and opposite reaction. when bumper cars crash into each other one car goes one way and the other goes the other way.
Q 25: if the bumper cars doubled their Mass the motion would be halfed but if the net force is doubled the motion will double.
First change km/ s into m/s, then use the formula
Lambda = velocity/ frequency
Answer:
The appropriate solution is "2.78 mm".
Explanation:
Given:

or,



or,

As we know,
Fringe width is:
⇒ 
hence,
Separation between second and third bright fringes will be:
⇒ 


or,

Answer:
These energy exchanges are not changes in kinetic energy. They are changes in bonding energy between the molecules. "If heat is coming into a substance during a phase change, then this energy is used to break the bonds between the molecules of the substance