Answer:
Explanation:
According to the law of conservation of linear momentum, the total momentum of both pucks won't be changed regardless of their interaction if no external forces are acting on the system.
Being 
and 
the masses of pucks a and b respectively, the initial momentum of the system is
Since b is initially at rest
After the collision and being 
and 
the respective velocities, the total momentum is
Both momentums are equal, thus
Solving for 
The initial kinetic energy can be found as (provided puck b is at rest)
The final kinetic energy is
The change of kinetic energy is
Answer:
The mass of the box:
m = 60 kg
Explanation:
Given:
F = 150 N
g = 10 m/s²
_________
m - ?
Coefficient of friction wood on wood:
μ = 0.25
Friction force:
F₁ = μ*m*g
Newton's Third Law:
F = F₁
F = μ*m*g
The mass of the box:
m = F / ( μ*g) = 150 / (0.25*10) = 60 kg
It is durable because it is one of the strongest metals and doesn't corrode easily.
The answer would be C. (:
Answer:
Please check the attached file for the diagram
Explanation:
The velocity of the of the rowboat 
through the river is the resultant velocity. It is obtained taking a vector sum of the velocity in still water and the velocity of the river.
There are several ways to take this vector sum, but the question makes it simple for us to use Pythagoras's theorem because the East and North directions are perpendicular to each other.
Hence;
