# AS Level Physics Topic 1 Chapter 1A Unit 1 Velocity and Acceleration

Hey! I was hoping someone would explain this question with its answer to me

*An electron in an X-ray machine is accelerated from rest to half the speed of light in 1.7×10^-15 s. Calculate:*

(A) the speed the electron reaches in m/s
(B)the acceleration the electron experiences

The answers in the book are: (a) 1.5×108 m/s (b)8.82×10²² m/s²
For A
Do you know the speed of light?
It is a constant that your exam board would provide in data booklet or sheet.

For B
Work from the definition of acceleration.

Acceleration = change of velocity / duration of time
Original post by Eimmanuel
For A
Do you know the speed of light?
It is a constant that your exam board would provide in data booklet or sheet.

For B
Work from the definition of acceleration.

Acceleration = change of velocity / duration of time

So is (a) (3×10⁸)÷2 ?
Original post by Eimmanuel
For A
Do you know the speed of light?
It is a constant that your exam board would provide in data booklet or sheet.

For B
Work from the definition of acceleration.

Acceleration = change of velocity / duration of time

And for (b) is the answer to question a÷1.7×10^-15 ?
Original post by Lamia5656
So is (a) (3×10⁸)÷2 ?

👍.
Original post by Lamia5656
And for (b) is the answer to question a÷1.7×10^-15 ?

If you mean (part a answer)÷ 1.7×10^-15, then yes. Good 👍.
Original post by Eimmanuel

If you mean (part a answer)÷ 1.7×10^-15, then yes. Good 👍.

Thanks!