Explanation:
Katherine Johnson, NASA Mathematician Featured in 'Hidden Figures,' Dies at 101
Feb 25, 2020 — Their story was told in the 2016 Hollywood film “Hidden Figures,” based on Margot Lee Shetterly's nonfiction book of the same title , ...
Explanation:
d= 80km = 8000m
t = 45 min = 45/60 h
= 0.75 h
V= ?
we know that,
V = d /t
or,V= 80 km / 0.75 h
- or, V= 106.67 km/hr
or,V= 106.67×1000m / 3600 s
2. or, V= 29.63 m/s
<span>Slowing an
object down is not a means of accelerating it. It actually decelerates the
motion of an object. Speeding it up, changing its direction and applying
balanced forces accelerate an object. In order for an object to accelerate, a force
must be applied. It follows Newton’s second law of motion where it states that
a body at rest remains at rest unless a force is acted upon it. When you move
an object, you are exerting a force onto it. By exerting a force on the object,
you are actually displacing it from its initial position. You cannot apply
force to the object without altering its position. Keep in mind that when you
exert work, you are exerting energy too. </span>
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.
Im not sure, but here are a few of mine : Learn to be silent, and listen, take massive action and be proactive, listen, focus, and lastly, persist. Hope this helped! (:
