Answer:
The theory of relativity usually encompasses two interrelated theories by Albert Einstein: special relativity and general relativity, proposed and published in 1905 and 1915, respectively. Special relativity applies to all physical phenomena in the absence of gravity.
Answer:
, in the direction of F2
Explanation:
The magnitude of F2 is larger than that of F1: this means that the wagon will tend to move in the direction of F2. Therefore, the direction of friction will be opposite to the direction of motion, therefore in the direction of F1.
Let's now take the direction of the force exerted by the second child, F2, as positive direction. Then the direction of F1 and of the force of friction () will be negative: so we have
We can write the equation of the forces for the third child+wagon:
where
m = 30.0 kg is the combined mass of the child + the wagon
Now we can solve the equation for a, to find the acceleration:
Answer:
No ejection of photo electron takes place.
Explanation:
When a photon of suitable energy falls on cathode, then the photoelectrons is emitted from the cathode. This phenomenon is called photo electric effect.
The minimum energy required to just eject an electron is called work function.
The photo electric equation is
E = W + KE
where, E is the incident energy, W is the work function and KE is the kinetic energy.
W = h f
where. h is the Plank's constant and f is the threshold frequency.
Now, when the violet light is falling, no electrons is ejected. When the red light is falling, whose frequency is less than the violet light, then again no photo electron is ejected from the metal surface.
Take more data. random errors can be evaluted through statistical analysis and can be reduce by average over a large number of observations. this is all i know im in middle school hope this help
For this case we have that by definition, the momentum is given by:
Where,
- <em>m: mass
</em>
- <em>v: speed
</em>
Therefore, replacing values we have:
From here, we clear the value of the speed:
Answer:
The magnitude of velocity is: