Answer:
minimum number of photon is 4.05 ×
Explanation:
given data
energy = 50 keV = 50 × eV = 50 ×
× 1.602×
J
thickness = 10^-3
contrast = 1%
to find out
number of incident photons
solution
we know here equation that is
E = n × h × ν .......................1
put here all these value
50 × = n × 6.6×
× c/ 1×
50 × × 1.602×
= n × 6.6×
×( 3 ×
/ 1×
)
solve it and find n
n = 4.05 ×
so here minimum number of photon is 4.05 ×
Answer:
Explanation:
In a LC circuit The time constant τ is the time necessary for 60% of the total current (maximum current), pass through the inductor after a direct voltage source has been connected to it. The time constant can be calculated as follows:
Therefore, the time needed for the current to reach a fraction f = 0.6(60%) of its maximum value is:
Answer:
The speed of player is given by
Explanation:
The time of flight for a projectile motion is given by
(i)
where t is the time of flight, v is the initial speed, and α is the angle.
Now the person must also reach the impact point of ball in the same time as above.
Now the total distance D the player needs to cover is basically R horizontal range of projectile minus the distance d, range R is given by,
Now the distance the player must cover is given by
D= R-d
D= - d
(ii)
Now the average speed of player is given by
(iii)
Replacing the values of D and T from eq. (i) and (ii) in eq. (iii).