Question

very small forces can have tremendous effects on the motions of every small object. an electron, mass 9.1 x 10 ^-31 kg, exerinces a force of 1.6 x 10^-17 N in a typical electric field at the earths surface. from rest,how much time would it take for the electron to reach the speed of 3.0 x 10^6 m/s?

Answer 1

t = 1.7 x 10⁻⁷ s

Step-by-step explanation:

Given,

The mass of the electron, m = 9.1 x 10⁻³¹ Kg

The force experienced by the electron, F = 1.6 x 10⁻¹⁷ N

The initial velocity of the electron, u = 0

The final velocity of electron, v = 3.0 x 10⁶ m/s

The acceleration of the electron is given by the relation

a = F/m

= 1.6 x 10⁻¹⁷ N / 9.1 x 10⁻³¹ Kg

= 1.76 x 10¹³ m/s²

Using the first equation of motion

v = u + at

t = (v - u) / a

= (3.0 x 10⁶ - 0) / 1.76 x 10¹³

= 1.7 x 10⁻⁷ s

Hence, the time taken by the electron to reach final speed is, t = 1.7 x 10⁻⁷ s