Answer:
When an object is in motion, there is energy associated with that object. Why should that be the case? Moving objects are capable of causing a change, or, put differently, of doing work. For example, think of a wrecking ball. Even a slow-moving wrecking ball can do a lot of damage to another object, such as an empty house. However, a wrecking ball that is not moving does not do any work
(hope it helps :p )
Answer:
Explanation:
Given
mass of bus along with travelers travelling in North direction is 
speed of bus towards North 
mass of bus travelling in South direction is 
speed of bus 
mass of each Passenger in south moving bus 
Momentum of North moving bus



Momentum with south moving bus


For total momentum to be towards south
should be greater than 0
thus for least value of n



NH4OH is the answer. Hope this helps you.
Answer:
4.44 rpm
Explanation:
= Angular speed
G = Gravitational constant = 6.67 × 10⁻¹¹ m³/kgs²
r = Radius of Europa = 
R = Radius of arm = 6 m
The acceleration due to gravity is given by

Here the centripetal acceleration of the arm and acceleration due to gravity are equal


Converting to rpm


The angular speed of the arm is 4.44 rpm