The electrical potential energy of a charge q located at a point at potential V is given by
Therefore, if the charge must move between two points at potential V1 and V2, the difference in potential energy of the charge will be
In our problem, the electron (charge e) must travel across a potential difference V. So the energy it will lose traveling from the metal to the detector will be equal to
Therefore, if we want the electron to reach the detector, the minimum energy the electron must have is exactly equal to the energy it loses moving from the metal to the detector:
<span>In the physics lab, a cube slides down a frictionless incline as shown in the figure below, check the image for the complete solution:
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Complete Question
In an action movie, the villain is rescued from the ocean by grabbing onto the ladder hanging from a helicopter. He is so intent on gripping the ladder that he lets go of his briefcase of counterfeit money when he is 130 m above the water. If the briefcase hits the water 6.0 s later, what was the speed at which the helicopter was ascending?
Answer:
The speed of the helicopter is 
Explanation:
From the question we are told that
The height at which he let go of the brief case is h = 130 m
The time taken before the the brief case hits the water is t = 6 s
Generally the initial speed of the briefcase (Which also the speed of the helicopter )before the man let go of it is mathematically evaluated using kinematic equation as
Here s is the distance covered by the bag at sea level which is zero
=>
=> 
=>
<u>Answer:</u>
Mass of base ball 
<u>Explanation:</u>
Circumference of baseball = 2πr = 23 cm
So radius of baseball = 3.66 cm = 
m
Mass per unit volume of baseball = Mass per unit volume of neutron or proton.
Mass of proton = 
kg
Diameter of proton = 
m
Radius of proton = 
m
Volume of ball = 
Now substituting all values in Mass per unit volume of baseball = Mass per unit volume of neutron or proton.
So mass of base ball
There are two possible answers:
<span>- it can move out to a higher electron shell
- </span><span> it can stay in its original shell
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In fact, sunlight consists of photons. When sunlight hits an electron, the electron can absorbs a photon, so it gains energy: as a result, the electron can move to a higher electron shell, which corresponds to a high energy level in the atom, if the energy given by the photon is at least equal to the energy difference between the two levels. However, if the photon energy is not large enough, the electron will stay in the same shell.</span>
