Question

a tv set shoots out a beam of electrons.the beam current is 10uA.how many electrons strike the tv screen in each second?how much charge strikes the screen in a minute?

Answer 1

we know that current is defined as rate of flow of electric charge through any cross section of conductor in unit time

i.e. if you say 10uA or
${10}^{ - 6} ampere \: = {10}^{ - 6}coulomb \: of \: charge \: per \: second$

for one minute
${10}^{ - 6} \times 60 = 6 \times {10}^{ - 5} coulomb$

Answer 2

Answer:

Explanation:

Given :-

Beam Current, I = 10 uA

Time, t = 1 seconds

To Find :-

Number of electrons Striking the TV screen per second

Charge striked to the screen in a minute.

Formula to be used :-

Q = I × t

Solution :-

Putting all the values, we get

Charge per second, Q = I × t

Charge per second, Q = 10 × 10⁻⁶ A × 1 s

Charge per second, Q = 10 × 10⁻⁶ C

Charge on an electron, Q = 1.6 × 10⁻¹⁹ C

No. of electrons Striking the TV screen per second,

= 10 × 10⁻⁶ C /  1.6 × 10⁻¹⁹ C

= 6.25 × 10¹³.

Charge Striking the screen per minute = 10 × 10⁻⁶ C × 60

Charge Striking the screen per minute = 6.0 × 10⁻⁴ C.

Hence, 6.25 × 10¹³ electrons strike the TV screen in each second and 6.0 × 10⁻⁴ C charge strikes the screen in a minute.