Answer:
Minimum number of photons required is 1.35 x 10⁵
Explanation:
Given:
Wavelength of the light, λ = 850 nm = 850 x 10⁻⁹ m
Energy of one photon is given by the relation :
....(1)
Here h is Planck's constant and c is speed of light.
Let N be the minimum number of photons needed for triggering receptor.
Minimum energy required for triggering receptor, E₁ = 3.15 x 10⁻¹⁴ J
According to the problem, energy of N number of photons is equal to the energy required for triggering, that is,
E₁ = N x E
Put equation (1) in the above equation.

Substitute 3.15 x 10⁻¹⁴ J for E₁, 850 x 10⁻⁹ m for λ, 6.6 x 10⁻³⁴ J s for h and 3 x 10⁸ m/s for c in the above equation.

N = 1.35 x 10⁵
Answer:
375 ms
Explanation:
the frequency of metronome , f = 160 beats per minute
f = 160 /60 beats per sec
f = 2.67 beats /s
the period of a single beat , T = 1/f
T = 1/2.67 s
T = 0.375 s = 375 ms
the period of a single beat is 375 ms
Force required to move a block is 1.615 N
Given:
mass of block = m = 150 pounds = 68 kg
distance = d = 5 ft = 1.52 metres
time = t = 8 sec
To Find:
force required to move the block
Solution: Force is defined as product of mass and acceleration and it's unit is N or Newton.
Velocity = displacement/ time = 1.52 / 8 = 0.19 m/s
Acceleration = velocity/time = 0.19/8 =
0.023 m/s^2
Force = mass x acceleration = 68x0.023 = 1.615 N
Hence, force required to move the block is 1.615 N
Learn more about Force here:
brainly.com/question/12970081
#SPJ4
Answer:
Option A) n
Explanation:
In accordance to Quantum Mechanical model of an atom:
- The Principle Quantum number (n) gives the description of the shell of an electron and the energy level of an electron in an atom.
- The angular momentum also referred to as Azimuthal Quantum number (l) gives the description of the shape of the orbitals and helps in determination of angular momentum magnitude.
- The magnetic quantum number (
) describes the energy levels or the number of orbitals contained in a subshell and the way these are oriented within.
- The spin quantum no. (
) determines the elelctron spin's direction which may be (
) or (
).
Period = (1/frequency) .
If frequency is 100 per second, then
Period = (1) / (100 per second) = 0.01 second .