Answer:
Nora's boat is moving towards Sam at 5 km/hr
Explanation:
The question says that Nora is few meters behind Nancy and is still with respect to her that means the relative velocity between Nora and Nancy is zero
Vrel = 5 - Vnora= 0 ⇒ Vnora = 5km/hr
Pictorially we can represent the given condition as:
Nora-------few meters------Nancy ----------------- Sam
5km/hr 5km/hr →
Hence, Nora's boat is moving towards Sam at 5km/hr.
Answer:
Explanation:
Given
Free fall acceleration on mars 
Time Period of pendulum on earth 
Time period of Pendulum is given by

for earth



(b)For same time period on mars length is given by



Answer:
It is easier to stop the bicycle moving at a lower velocity because it will require a <em>smaller force</em> to stop it when compared to a bicycle with a higher velocity that needs a<em> bigger force.</em>
Explanation:
The question above is related to "Newton's Law of Motion." According to the <em>Third Law of Motion</em>, whenever an object exerts a force on another object <em>(action force)</em>, an equal force is exerted against it. This force is of the same magnitude but opposite direction.
When it comes to moving bicycles, the force that stops their movement is called "friction." Applying the law of motion, the higher the speed, the higher the force<em> </em>that is needed to stop it while the lower the speed, the lower the force<em> </em>that is needed to stop it.