Answer:
Explanation:
Threshold frequency = 4.17 x 10¹⁴ Hz .
minimum energy required = hν where h is plank's constant and ν is frequency .
E = 6.6 x 10⁻³⁴ x 4.17 x 10¹⁴
= 27.52 x 10⁻²⁰ J .
wavelength of radiation falling = 245 x 10⁻⁹ m
Energy of this radiation = hc / λ
c is velocity of light and λ is wavelength of radiation .
= 6.6 x 10⁻³⁴ x 3 x 10⁸ / 245 x 10⁻⁹
= .08081 x 10⁻¹⁷ J
= 80.81 x 10⁻²⁰ J
kinetic energy of electrons ejected = energy of falling radiation - threshold energy
= 80.81 x 10⁻²⁰ - 27.52 x 10⁻²⁰
= 53.29 x 10⁻²⁰ J .
The answer would be a.
a chemical change is a change to the chemical makeup of a substance so if the bonds are unchanged it would be a characteristic of a physical change
It would have to be 36,719 Km high in order to be to be in geosynchronous orbit.
To find the answer, we need to know about the third law of Kepler.
<h3>What's the Kepler's third law?</h3>
- It states that the square of the time period of orbiting planet or satellite is directly proportional to the cube of the radius of the orbit.
- Mathematically, T²∝a³
<h3>What's the radius of geosynchronous orbit, if the time period and altitude of ISS are 90 minutes and 409 km respectively?</h3>
- The time period of geosynchronous orbit is 24 hours or 1440 minutes.
- As the Earth's radius is 6371 Km, so radius of the ISS orbit= 6371km + 409 km = 6780km.
- If T1 and T2 are time period of geosynchronous orbit and ISS orbit respectively, a1 and a2 are radius of geosynchronous orbit and ISS orbit, as per third law of Kepler, (T1/T2)² = (a1/a2)³
- a1= (T1/T2)⅔×a2
= (1440/90)⅔×6780
= 43,090 km
- Altitude of geosynchronous orbit = 43,090 - 6371= 36,719 km
Thus, we can conclude that the altitude of geosynchronous orbit is 36,719km.
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4200 N is the tension in the cable that pulls the elevator upwards.
The correct option is A.
<h3>What does tension ?</h3>
Tension is the force that is sent through a rope, thread, or wire whenever two opposing forces pull on it. Along the whole length of the wire, the tensile stress pulls equally on all objects at the ends. Every physical object that comes into contact with that other one exerts force on it.
<h3>Briefing:</h3>
We employ the following formula to determine the cable's tension.
Formula:
T = mg+ma............ Equation 1
Where:
T is the cable's tension.
M = Mass of the elevator and the Joey
Accelerating with a
g = Gravitational acceleration
Considering the query,
Given:
m = (300+60) = 360 kg
a = 2 m/s²
g = 9.8 m/s²
Substitute these values into equation 2
T = (360×9.8)+(360×2)
T = 3528+720
T = 4248 N
T ≈ 4200 to the nearest hundred.
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Yes. It r<span>efers to any of the temperatures assigned to a number of reproducible equilibrium states on the International Practical Temperature Scale</span><span>
In short, Your Answer would be "True"
Hope this helps!</span>
