Answer:
What are we supposed to find, if it is kinetic energy then this is the solution.
K.E=1/2mv^2
K.E= kinetic energy
M=mass
V=velocity
K.E =0.5*55*0.6^2
K.E=9.9J
Explanation:
If you were given distance & period of time, you would be able to calculate the speed.
Hope this helps!
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
I think it’s going to be the 2nd one
Answer:
Explanation:
E₀ = 229.1 V/m
E = E₀ / √2 = 229.1 / 1.414 = 162 V/m
B = E / c ( c is velocity of em waves )
= 162 / (3 x 10⁸) = 54 x 10⁻⁸ T
rate of energy flow = ( E x B ) / μ₀
= 162 x 54 x 10⁻⁸ / 4π x 10⁻⁷
= 69.65 W per m².