Answer:
4.71 eV
Explanation:
For an electromagnetic wave with wavelength
the energy of the photons in the wave is given by
where h is the Planck constant and c the speed of light. Therefore, this is the minimum energy that a photon should have in order to extract a photoelectron from the copper surface.
The work function of a metal is the minimum energy required by the incident light in order to extract photoelectrons from the metal's surface. Therefore, the work function corresponds to the energy we found previously. By converting it into electronvolts, we find:
Answer: 1. 0.25 m/s squared
2. A = 0.4 m/s^2
3.=20kg. I did this before.
Explanation:
Mantle convection<span> is the slow creeping motion of Earth's solid silicate </span>mantle<span> caused by </span>convection<span> currents carrying heat from the interior of the Earth to the surface.
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<h2>
Answer: Heat transfer by radiation</h2>
Explanation:
There are three ways in which the thermal transfer (heat) occurs:
1. By Conduction, when the transmission is by the <u>direct contact.</u>
2. By Convection, heat transfer<u> in fluids</u> (like water or the air, for example).
3. By <u>Radiation</u>, by the electromagnetic waves (they can travel through any medium and in vacumm or empty space)
Since outter space is vacuum (sometimes called "empty"), energy cannot be transmitted by convection, nor conduction. It must be transmitted by electromagnetic waves that are able to travel with or without a medium.
Answer:
1 - third law
2 - second law
3 - first law
4 - third law
5 - second law
6 - first law
Explanation:
First law
In an inertial frame of reference, an object either remains at rest or continues to move at a constant velocity, unless acted upon by a force.
Second law
In an inertial frame of reference, the vector sum of the forces F on an object is equal to the mass m of that object multiplied by the acceleration, a of the object
F = ma.
Third law
When one body exerts a force on a second body, the second body simultaneously exerts a force equal in magnitude and opposite in direction on the first body.
