Answer:
Coefficient of friction between the book and floor is 0.582.
Explanation:
Using the velocity formula;
v^2 = 2as
a = v^2/(2s)
a = 1.6^2/(2*0.9)
a = 2.56/1.8
a = 1.42 m/s^2
the force necessary to give the book the acceleration is
F = ma = 3.5*1.42 (m is mass of the book i.e. 3.5 kg)
F = 4.98 N
The difference in the force is the friction force, which is
Ff = 25 - 4.98 = 20 N
Ff = mgμ
where μ is coefficient of friction and g is acceleration due to gravity that is 9.8 m/s^2
μ = Ff/mg
μ = 20/(3.5*9.81)
μ = 0.582
Coefficient of friction between the book and floor is 0.582.
The fact is your rooftop is covered with dust particles from meteorites. Outerspace is full of debris. Every day, thousands of meteorites invade our home but thanks to atmosphere for keeping us safe from them :D
When these meteorites enter our atmosphere, they experience resistance to the particles present in our atmosphere. As a result they catch fire(and eventually melts) and lose all their energy before falling on the surface. This happens with very small sized meteorites but when bigger ones enter, they surely hit the surface because they are difficult to melt.
Thanks to Jupiter for saving us from asteroids. Bigger ones rarely enters our atmosphere because of Jupiter's gravitational pull. It lures all the debris towards itself (:
A) all because of the movement, and friction involved with the movement.
The answer is Polar covalent. btw, this is chemistry work. not physics