Explanation:
It is given that,
Wavelength of red light, 
Power of the laser, 
(a) The energy carried by each photon is given by :


(b) Let n is the number of photons emitted by the laser per second. It can be calculated as :


Hence, this is the required solution.
Answer:
Initial Velocity = 0 m/s
Final Velocity = 34.6 m/s
time = 3.5 s
Explanation:
The initial velocity must be zero since, the egg must be at rest initially, before dropping.
<u>Initial Velocity = 0 m/s</u>
Now, for time we use 2nd equation of motion:
h = Vi t + (1/2)gt²
where,
h = Height = 61 m
Vi = Initial Velocity = 0 m/s
g = 9.8 m/s²
t =time = ?
Therefore,
61 m = (0 m/s)(t) + (1/2)(9.8 m/s²)t²
t² = (61 m)(2)/(9.8 m/s²)
t = √(12.45 s²)
<u>t = 3.5 s</u>
Now, for final velocity we will use 1st equation of motion:
Vf = Vi + gt
Vf = 0 m/s + (9.8 m/s²)(3.5 s)
Vf = 34.6 m/s
Neon (10)
Sodium (11)
Silicon (14)
Iron (26)
Uranium (92)
Explanation:
It is given that,
Initial speed of the broad jump, u = 12 m/s
It is launched at an angle of 20 degrees above the horizontal. Let t is the time for which the track star i in the air before returning to Earth. The motion of the track star in the broad jump can be treat as the projectile motion. The time of flight of the projectile is given by :

Putting all the values in above equation as :

t = 0.837 seconds
So, the time for which the track star is in air is 0.837 seconds. Hence, this is the required solution.