Answer:
n = 4 x 10¹⁸ photons
Explanation:
First, we will calculate the energy of one photon in the radiation:

where,
E = Energy of one photon = ?
h = Plank's Constant = 6.625 x 10⁻³⁴ J.s
c = speed of light = 3 x 10⁸ m/s
λ = wavelength of radiation = 567 nm = 5.67 x 10⁻⁷ m
Therefore,

E = 3.505 x 10⁻¹⁹ J
Now, the number of photons to make up the total energy can be calculated as follows:

<u>n = 4 x 10¹⁸ photons</u>
Answer:
M_Train>> m_car a_train <a_car
Explanation:
To start the movement of the train or the car, the motorcycle applies a force on the wheels, which starts the acceleration in the case of the train, it has a much greater mass than that of the car, for which to obtain the same acceleration necessary a much greater force
a = F / m
as the mass of the train is greater than that of the car.
a_train <a_car
Something similar happens when the vehicles stop, the engine stops applying force forward and the brakes apply a force backward that creates a negative acceleration that slows down, again as the mass of the train is much greater than the of the car its negative acceleration is much less.
It is good to clarify that to compensate for this the trains have a braking system on all wheels
The work done by the normal force n when the box slides down a frictionless incline and gaining speed is zero.
<h3>What is normal force?</h3>
The force of contact is called the normal force. When the two surfaces are in contact with each other, then the normal force acts.
This force is applied by the solid bodies on each other in order to prevent the passing through each other.
A box slides down a frictionless incline, gaining speed. For this box, the value of work done by normal force has to be found out. Let's analyze the given condition.
- The body is gaining the speed, which means there is a change in kinetic energy.
- The change in kinetic energy is equal to the work done.
- The friction force is the product of coefficient of the friction and normal force.
- The friction force for the given case is zero. Thus, the normal force must be equal to the zero.
Thus, the work done by the normal force n when the box slides down a frictionless incline and gaining speed is zero.
Learn more about the normal force here;
brainly.com/question/10941832
Answer: 0.25 m/s
Explanation: Speed = wavelengt · frequency
v = λf and frequency is 1/period f = 1/T
Then v = λ/T = 5 m / 20 s = 0.25 m/s