Deflecting an Electron Between Charged Plates

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1. Question 1

   An electron ($e = 1.602\times10^{-19}\ \text{C}$, $m = 9.11\times10^{-31}\ \text{kg}$) is in a uniform field of magnitude $2.5\times10^{3}\ \text{N/C}$. Find the size of its acceleration, in units of $10^{14}\ \text{m/s}^2$ to three significant figures.

   $a =$×10¹⁴ m/s²

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2. Question 2

   An electron ($e = 1.602\times10^{-19}\ \text{C}$, $m = 9.11\times10^{-31}\ \text{kg}$) enters plates $L_1 = 6.0\ \text{cm}$ long horizontally at $v_0 = 3.0\times10^{7}\ \text{m/s}$; the field between them has magnitude $1.0\times10^{3}\ \text{N/C}$. Find its vertical speed as it leaves, in units of $10^{5}\ \text{m/s}$ to three significant figures.

   $v_y =$×10⁵ m/s

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3. Question 3

   An electron ($e = 1.602\times10^{-19}\ \text{C}$, $m = 9.11\times10^{-31}\ \text{kg}$) crosses plates $L_1 = 5.0\ \text{cm}$ long at $v_0 = 2.5\times10^{7}\ \text{m/s}$ in a field of magnitude $2.0\times10^{3}\ \text{N/C}$. Find $\tan\theta_1$ of its exit angle, to three significant figures.

   $\tan\theta_1 =$

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4. Question 4

   An electron with kinetic energy $K = 1.6\ \text{keV}$ passes plates $L_1 = 2.0\ \text{cm}$ long with field $E_y = 8.0\times10^{3}\ \text{N/C}$; the screen is $L_2 = 15\ \text{cm}$ beyond them. Find the deflection on the screen, in centimetres.

   $y =$cm

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5. Question 5

   Electrons of kinetic energy $2.0\ \text{keV}$ pass between deflecting plates and land $1.5\ \text{cm}$ from the undeflected spot on a screen. The kinetic energy is raised to $5.0\ \text{keV}$ and the field between the plates is made $1.6$ times as strong, with the same plates and screen. Find the new deflection, in centimetres to two significant figures.

   $y' =$cm

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