There's no such thing as "stationary in space". But if the distance
between the Earth and some stars is not changing, then (A) w<span>avelengths
measured here would match the actual wavelengths emitted from these
stars. </span><span>
</span><span>If a star is moving toward us in space, then (A) Wavelengths measured
would be shorter than the actual wavelengths emitted from that star.
</span>In order to decide what's actually happening, and how that star is moving,
the trick is: How do we know the actual wavelengths the star emitted ?
Hello!
Answer: 7918 J
Explanation:
We are assuming that the floor (field) is completely horizontal since there's no information about that in the statement.
We are going to use the following formula:

Where:


º

Then, by substituting we have:

Answer: True
Explanation: Because of the way this water cycle has always circulated our planet, there is indeed a chance that the water in your glass is the same water that thirsty dinosaurs were drinking about 65 million years ago
Answer:

Explanation:
d = Diameter of spot = 30 μm
r = Radius of spot = 
P = Power of the laser = 
A = Area = 
Intensity is given by

The light intensity within this spot is 
Answer:
Momentum of block B after collision =
Explanation:
Given
Before collision:
Momentum of block A =
= 
Momentum of block B =
= 
After collision:
Momentum of block A =
= 
Applying law of conservation of momentum to find momentum of block B after collision
.

Plugging in the given values and simplifying.


Adding 200 to both sides.


∴ 
Momentum of block B after collision =