Answer:
V=972π
The equation I used... V=4/3π(9)^3
Answer:
Explanation:
Since both vectors are pointing on the same direction (Northeast), the sum of them will point in that same direction, and its magnitud will be the sum of the magnitudes of each vector (40m/s2+10m/s2). This problem is just a problem in one dimension. The sum of the vectors is then 50m/s2 Northeast.
Answer:
c. The incident light must have at least as much energy as the electron work function
Explanation:
In photoelectric effect, electrons are emitted from a metal surface when a light ray or photon strikes it. An electron either absorbs one whole photon or it absorbs none. After absorbing a photon, an electron either leaves the surface of metal or dissipate its energy within the metal in such a short time interval that it has almost no chance to absorb a second photon. An increase in intensity of light source simply increase the number of photons and thus, the number of electrons, but the energy of electron remains same. However, increase in frequency of light increases the energy of photons and hence, the
energy of electrons too.
Therefore, the energy of photon decides whether the electron shall be emitted or not. The minimum energy required to eject an electron from the metal surface, i.e. to overcome the binding force of the nucleus is called ‘Work Function’
Hence, the correct option is:
<u>c. The incident light must have at least as much energy as the electron work function</u>
The potential energy of the object is going to be gravitational: PE=mgh. Assuming we're talking about the gravitational potential energy relative to the bottom of the cliff, the object's height is 30 m. g is 9.8 m/s^2. We don't know its mass. You could technically use the equation F=mg to find the mass, where F=40 and g=9.8, but that's unnecessary. You can just substitute F into PE=mgh to get PE=Fh. Substitute the given values to get PE=40*30=120 J.
