In a TV picture tube electrons are ejected from the cathode with negligible speed and reach a velocity of 5 - 106 m - s in travelling one centimeter- Assuming straight line motion- find the constant force exerted on the electron- The mass of the electron is 9-1 - 10-31 kg-

Given, Initial velocity , u = 0 (negligible) v = 5 × 10^6 m/s S= 1 cm = 1 × 10^ 2 m ∴ Acceleration , a = v^2 u^2/2S = (5 × 10^5)^2 ...

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Standard XII

Physics

Com of Solid Bodies

In a TV pictu...

Question

In a TV picture tube electrons are ejected from the cathode with negligible speed and reach a velocity of $5 \times 10^{6} m / s$ in travelling one centimeter. Assuming straight line motion, find the constant force exerted on the electron. The mass of the electron is $9.1 \times 10^{- 31} k g .$

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Solution

Given, Initial velocity , u = 0 (negligible)

v = $5 \times 10^{6} m / s$

S= 1 cm = $1 \times 10^{- 2} m$

$∴$ Acceleration , $a = \frac{v^{2} - u^{2}}{2 S}$

= $\frac{(5 \times 10^{5})^{2} - 0}{2 \times I \times 10^{- 3}}$

= $\frac{25 \times 10^{12}}{2 \times 10^{- 2}}$

$= 12.5 \times 10^{14} m / s^{2}$

and Force , F = ma

= $9.1 \times 10^{- 31} \times 12.5 \times 10^{- 14}$

= $113.75 \times 10^{- 12}$

= $1.1 \times 10^{- 16} N$

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In a TV picture tube electrons are ejected from the cathode with negligible speed and reach a velocity of 5×106m/s in travelling one centimeter. Assuming straight line motion, find the constant force exerted on the electron. The mass of the electron is 9.1×10−31kg.

Given, Initial velocity , u = 0 (negligible) v = 5×106m/s S= 1 cm = 1×10−2m ∴ Acceleration , a=v2−u22S = (5×105)2−02×I×10−3 = 25×10122×10−2 =12.5×1014m/s2 and Force , F = ma = 9.1×10−31×12.5×10−14 = 113.75×10−12 = 1.1×10−16N

In a TV picture tube electrons are ejected from the cathode with negligible speed and reach a velocity of $5 \times 10^{6} m / s$ in travelling one centimeter. Assuming straight line motion, find the constant force exerted on the electron. The mass of the electron is $9.1 \times 10^{- 31} k g .$