Answer:
Approximately 
.
(Assuming that 
.)
Explanation:
The mechanical energy of an object is the sum of its potential energy and its kinetic energy. It will be shown that the exact mass of this object doesn't matter. For ease of calculation, let 
represent the mass of the book.
The initial potential energy of the book is
.
The book was initially at rest when it was released. Hence, its initial kinetic energy would be zero. Hence, the initial mechanical energy of the book-Earth system would be 
.
When the book was about to hit the ground, its speed is 
. Its kinetic energy would be:
.
The question implies that the potential energy of the book near the ground is zero. Hence, the mechanical energy of the system would be 
when the book was about to hit the ground.
The amount of mechanical energy lost in this process would be equal to:
.
Divide that with the initial mechanical energy of the system to find the percentage change. Note how the mass of the book, , was eliminated in this process.
.
Answer:
The effect of this rotation on the person on the surface is the sky is moving, like an apparent diurnal motion.
Explanation:
<em>For an observer at a fixed position on Earth, the rotation of earth makes it appear as if the sky is revolving around the earth. In other words, if a person is standing for long enough in a field at night, it looks like the sky is moving, not the person. This motion is called "apparent diurnal motion." </em>
<em>Diurnal means having to do with a day, in a sense of a 24- hour period.</em>
<span>θ=0.3sin(4t)
w=0.3cost(4t)(4)=1.2cost(4t)
a=-4.8sin(4t)
cos4t max will always be 1 (refer to cos graph), for same reason, sin4t will always be 0
therefore, wmax=1.2rad/s
vAmax=r*w=250*1.2=300mm/s
(may be different if your picture/radius is from a different picture)
adt=a*r=200*-4.8sin(4t)=0 (sin(4t)=0)
adn=r*w^2=200*1.2^2=288
ad= square root of adt^2+adn^2 = 288mm/s^2</span>
B is the correct answer
y=Asin(wt-kx)
A=amplitude
f=frequency
x=wavelength
since refraction is not on the wave formula,then option B is the correct answer
Average speed equal to = ,total distance traveled/total time taken
so it would be = 94+84/8
= 22.25 kmph
