Answer:
511.1 J
Explanation:
We are given that
Mass of wood block=m=3 kg
Vertical distance,h=23 m
Horizontal distance =x=30 m
Distance traveled in downward direction y=40 m
Initial velocity,u=0
Where 
By work energy theorem
Change in kinetic energy=Work done= mgh-W
Hence, the work done due to friction on the block as it slides down the ramp=511.1 J
We are asked to solve for the index of refraction and the formula is n = c/v where "n" represents the index of refraction, "c" represents the speed of light in the vacuum while "v" represents the speed of another medium.
In the problem, we have the given values below:
c = 3 x 10^8 m/s
v = 2 x 10^8 m/s
n =?
Solving for n, we have the solution below:
n = 3x10^8 / 2x10^8
n = 1.5
The answer is 1.5 for the index of refraction.
A second important difference between comets coming from the Kuiper Belt and from the Oort cloud is represented by their different characteristic periods.
In fact, short period comets are thought to generate in the Kuiper belt and have rather predictable orbits with short periods (up to 200 years). There are two major families of short period comets: the Jupiter family with periods of less than 20 years and the Halley family with periods form 20 to 200 years. That's short
Answer:
Dark matter does not affect our view, humans can see through them.
Explanation:
They do not affect our view because we can see right through the (weakly interacting) dark matter, as they do not interact or interfere with electromagnetic force.
Dark matter are often invisible substances and are difficult to spot because they don't absorb or reflect light.
The answer is :78 I think
