Answer:
163.33 Watts
Explanation:
From the question given above, the following data were obtained:
Mass (m) = 40 Kg
Height (h) = 25 m
Time (t) = 1 min
Power (P) =..?
Next, we shall determine the energy. This can be obtained as follow:
Mass (m) = 40 Kg
Height (h) = 25 m
Acceleration due to gravity (g) = 9.8 m/s²
Energy (E) =?
E = mgh
E = 40 × 9.8 × 255
E = 9800 J
Finally, we shall determine the power. This can be obtained as illustrated below:
Time (t) = 1 min = 60 s
Energy (E) = 9800 J
Power (P) =?
P = E/t
P = 9800 / 60
P = 163.33 Watts
Thus, the power required is 163.33 Watts
Answer:
B. Maximum velocity of ejected electrons.
Explanation:
The ejection of electrons form a metal surface when the metal surface is exposed to a monochromatic electromagnetic wave of sufficiently short wavelength or higher frequency (or equivalently, above a threshold frequency), which leads to the enough energy of the wave to incident and get absorbed to the exposed surface emits electrons. This phenomenon is known as the photoelectric effect or photo-emission.
The minimum amount of energy required by a metal surface to eject an electron from its surface is called work function of metal surface.
The electrons thus emitted are called photo-electrons.
The current produced as a result is called photo electricity.
Energy of photon is given by:

where:
h = Planck's constant
frequency of the incident radiation.
The electrons are already there. They are freely moving through the conductor.
Answer:
2,87 * 
Explanation:
When the bullets meet at the center and collide, since momentum is a vectoral quantity, their momentum vectors even up and are sumof zero. Formula of momentum is P = m.v , where m is mass and v is velocity. Let’s name the first two bullets as x,y and the one which mass is unknown as z. Then calculate momentum of x and y:
Px= 5,30 *
* 301 = 1,5953 kg*m/s
Py= 5,30 *
* 301 = 1,5953 kg*m/s
The angle between x and y bullets is 120°, and we know that if the angle between two equal magnitude vectors is 120°, the magnitude of the resultant vector will be equal to first two and placed in exact middle of two vectors. So we can say total momentum of x and y (Px+Py) equals to 1,5953 kg*m/s as well (Shown in the figure).
For z bullet to equalize the total momentum of x and y bullets, it needs to have the same amount of momentum in the opposite way.
Pz = 1,5953 = m * 554
m = 2,87 *
kg
Answer:
natural motion and violent motion
Explanation: