Answer:
Ultraviolet radiation would yield more electrical energy
Explanation:
The reason for the ultraviolet to generate more energy is that there would be getting more electrons per unit of time the photovoltaic cell, due to the higher frequency of the ultraviolet in comparison with the infrared radiation.
The infrared spectrum goes from 300 GHz (10^9 Hertz) to 400 THz or (10^12 Hertz).
The ultraviolet spectrum goes from 800 THz to 30.000 THz or (10^12 Hertz). This kind of radiation is responsible for skin burn from the sun and it´s the “ most usable” part from the sunlight in a photovoltaic cell.
Answer:
a) 3.0×10⁸ m
b) 0 m
Explanation:
Displacement is the distance from the starting position to the final position.
a) In half a year, the Earth travels from one point on the circle to the point on the exact opposite side of the circle (from 0° to 180°). The distance between the points is the diameter of the circle.
x = 2r
x = 2 (1.5×10⁸ m)
x = 3.0×10⁸ m
b) In a full year, the Earth travels one full revolution, so it ends up back where it started. The displacement is therefore 0 m.
Answer: 80 Newton
Explanation:
Initial velocity of ball = +20 m/s.
Final velocity of ball = -20 m/s
Mass of ball = 0.1kg
Time taken = 0.05 seconds
Average force = (Change in momentum of moving ball / Time taken)
Since, change in momentum = Mass (final velocity - initial velocity)
Change in momentum =0.1 x (-20 - (+20))
= 0.1 x (-20-20)
= 0.1 x (-40)
= -4.0 kgm/s
Then, put -4.0 kgm/s in the equation of force when Average Force = (Change in momentum / Time taken)
= (-4.0kgm/s / 0.05 seconds)
= 80Newton (note that the negative sign does not reflect on the magnitude of force)
Thus, the average force exerted on the ball is 80N
D. Rutherford found that the atom consists of a small positively charged nucleus.
