Answer:
Parachute exerts a force of 619.2 N upward
The net force is 86.4 N acting downward
Explanation:
As the gravitational acceleration g = 9.8 m/s2, the parachute help reduces the net acceleration to 1.2m/s. So it must exerted an upward acceleration on the skydiver of
9.8 - 1.2 = 8.6 m/s2
Since the skydiver mass is 72 kg, we can use Newton's 2nd law to calculate the force that causes this acceleration of 8.6
F = ma = 8.6*72 = 619.2 N acting upward
The net force is also the product of net acceleration and mass
= 1.2 * 72 = 86.4 N acting downward
The number of electrons emitted from the metal per second increases if the intensity of the incident light is increased.
Answer: Option B
<u>Explanation:</u>
As a result of photoelectric effect, electrons are emitted by the light incident on a metal surface. The emitted electrons count and its kinetic energy can measure as the function of light intensity and frequency. Like physicists, at the 20th century beginning, it should be expected that the light wave's energy (its intensity) will be transformed into the kinetic energy of emitted electrons.
In addition, the electrons count emitting from metal must vary with light wave frequency. This frequency relationship was expected because the electric field oscillates due to the light wave and the metal electrons react to different frequencies. In other words, the number of electrons emitted was expected to be frequency dependent and their kinetic energy should be dependent on the intensity (constant wavelength) of light.
Thus, the maximum in kinetic energy of electrons emitted increases with increase in light's frequency and is experimentally independent of light intensity. So, the number of emitted electrons is proportionate to the intensity of the incident light.
Answer: D
Explanation:
Atomic weight is measured by adding the number of protons and neutrons in an atom's nucleus. Argon's atomic number is 18 while potassium's is 19. This means that Argon will always have 18 protons while potassium will always have 19 protons.
To make the numbers easier to work with, round each atomic weight. We'll say the atomic weight of potassium is 39 and the atomic weight of argon is 40. To see how many neutrons each one has, I can set up a simple equation for each using the following equation:
Atomic weight = protons + neutrons
Potassium:
39 = 19 + N --> N = 20
Argon:
40 = 18 + N --> N = 22
An atom is defined by the number of protons it has, but the number of neutrons can vary. We call these isotopes, or atoms with the same number of protons but a different number of neutrons. As the math shows, argon typically has more neutrons per atom than potassium does.
Answer: I am getting a result around the 54,800 area, so I am selecting the 55,000 HP answer.
<span>O + Na + Cl = NaClO
Reactants :
O -> </span><span>Oxygen
</span><span>
Na -> Sodium
Cl-> Chlorine
hope this helps!
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