Is 1.875×10^8 m/s² the Correct Acceleration for the Electron in the TV Tube?

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The discussion centers on calculating the acceleration of an electron in a TV picture tube, where the electron travels 1.20 cm and reaches a speed of 4.50×10^6 m/s. The equation v^2 = u^2 + 2as is used to find acceleration, but the initial calculation of 1.875×10^8 m/s² is deemed incorrect. Participants emphasize the importance of using SI units for accurate results and suggest that acceleration must be determined before calculating time and net force. The correct approach involves substituting values into the equations after proper unit conversion.
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1. An electron of mass 9.11×10^−31 kg leaves one end of a TV picture tube with zero initial speed and travels in a straight line to the accelerating grid, which is a distance 1.20 cm away. It reaches the grid with a speed of 4.50×10^6 m/s. The accelerating force is constant.
Find the acceleration.
Find the time to reach the grid.
Find the net force. (ignore gravity on the electron)




2. v^2=(u^2)+2*a*s



3. I plugged in the numbers to the equation v^2=(u^2)+2*a*s. to find acceleration, but the anwer (1.875*10^8) was incorrect. Is this the correct equation? The other answers should stem from the acceleration right?
 
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(4.50×10^6 m/s.)^2 = 2*a*(1.2x10^-2)
From the above equation find the value of a
 
Acceleration - Sub into equation v2=u2+2aS -- make sure you only substitute after converting to SI units.

Time - Use Equation a=(v-u)/t (Yes you need to find acceleration first)

Net force - Use equation \sumF=ma

And 1.875*10^8 for acceleration is wrong.

Hope this helps.
 
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