I’m lost at this question, sorry but I would’ve help !
Assuming that the object starts at rest, we know the following values:
distance = 25m
acceleration = 9.81m/s^2 [down]
initial velocity = 0m/s
we want to find final velocity and we don't know the time it took, so we will use the kinematics equation without time in it:
Velocity final^2 = velocity initial^2 + 2 × acceleration × distance
Filling everythint in, we have:
Vf^2 = 0^2 + (2)(-9.81)(-25)
The reason why the values are negative is because they are going in the negative direction
Vf^2 = 490.5
Take the square root of that
Final velocity = 22.15m/s which is answer c
Explanation:
It is given that,
Bandwidth of a laser source, 
(b) Let t is the time separation of sections of sections of the light wave that can still interfere. The time period is given by :



(a) Let h is the coherence length of the source. It is given by :

c is the speed of light

l = 0.0099 m
Hence, this is the required solution.
Answer:
Because here is a number of electrons more applied to the balloon