Calculating Electron Speed in a TV Screen Using 2.0 kV Potential Difference

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Electrons in a television set are accelerated by a potential difference of 2.0 kV, and their speed can be calculated using the formula derived from energy conservation principles. The work done on the electron by the potential difference equals the change in kinetic energy, expressed as (1/2)mv² = qΔV. To find the speed, one must first convert the potential difference into joules using the charge of the electron. The discussion emphasizes ignoring relativistic effects for this calculation, simplifying the process. Understanding electric potential and energy changes is crucial for solving the problem effectively.
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Electrons in a television set are accelerated through a potential difference of 2.0 kV.
(a) Find the speed of the electrons when they reach the screen. Ignore any relativistic effects.

how to do this i have no idea what formula to use
 
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hotstuff said:
Electrons in a television set are accelerated through a potential difference of 2.0 kV.
(a) Find the speed of the electrons when they reach the screen. Ignore any relativistic effects.

how to do this i have no idea what formula to use
What is the definition of electric potential? The problem tells you how much the electron's electric potential will change. How much will its potential energy change? How much will its kinetic energy change? Assume the electron starts at test. How much velocity does it acquire?
 
hotstuff said:
Electrons in a television set are accelerated through a potential difference of 2.0 kV.
(a) Find the speed of the electrons when they reach the screen. Ignore any relativistic effects.

how to do this i have no idea what formula to use
check here:
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/ev.html#c2
see above URL page to find (for charge initially at rest):
(work done on charge q by potential difference ΔV) = (1/2)mv2 = qΔV

other concepts you may need later:
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/elewor.html#c1
 
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The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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