Answer:
a. by moving the book without acceleration and keeping the height of the book constant
Explanation:
FOR CONSTANT KINETIC ENERGY:
The kinetic energy of a body depends upon its speed according to its formula:
ΔK.E = (1/2)mΔv²
So, for Δv = 0 m/s
ΔK.E = 0 J
So, for keeping kinetic energy constant, the books must be moved at constant speed without acceleration.
FOR CONSTANT POTENTIAL ENERGY:
The potential energy of a body depends upon its height according to its formula:
ΔP.E = mgΔh
So, for Δh = 0 m/s
ΔP.E = 0 J
So, for keeping potential energy constant, the books must be moved at constant height.
So, the correct option is:
<u>a. by moving the book without acceleration and keeping the height of the book constant</u>
Answer:
B
Explanation:
because atoms make up an element.
Answer:
The minimum thickness = 83.92 nm
Explanation:
The relation between the wavelength in a particular medium and refractive index 
where ;
= wavelength of the light in vacuum
n = refractive index of medium with respect to vacuum
For one phase change :
Replacing 1.43 for n and 480 nm for λ; we have:
t = 83.92 nm
Thus; the minimum thickness = 83.92 nm
Answer:
Explanation:
The relation between time period of moon in the orbit around a planet can be given by the following relation .
T² = 4 π² R³ / GM
G is gravitational constant , M is mass of the planet , R is radius of the orbit and T is time period of the moon .
Substituting the values in the equation
(.3189 x 24 x 60 x 60 s)² = 4 x 3.14² x ( 9380 x 10³)³ / (6.67 x 10⁻¹¹ x M)
759.167 x 10⁶ = 8.25 x 10²⁰ x 39.43 / (6.67 x 10⁻¹¹ x M )
M = .06424 x 10²⁵
= 6.4 x 10²³ kg .
Answer:
The distance traveled in 1 year is: 
Explanation:
Given
--- speed
--- time
Required
The distance traveled
This is calculated as:
So, we have:
This gives:
-- approximated
