need help...
A proton moves in an electric field such that its acceleration (in cms-2) is
A = −20(1 + 2t)^-2, where t is in seconds.
Find the velocity as a function of time if v = 30 cms^-1 when t = 0.

Question

need help...
A proton moves in an electric field such that its acceleration (in cms-2) is 
A = −20(1 + 2t)^-2, where t is in seconds. 
Find the velocity as a function of time if v = 30 cms^-1 when t = 0.

ganeshie8 · Answer

What do you know about acceleration ?

welshfella · Answer

how is acceleration related to velocity?

samhang · Answer

no idea! I found this problem...

mecharv · Answer

Acceleration is the rate of change of velocity? The first derivative of velocity is acceleration. 
Is that right?

welshfella · Answer

yes - first derivative of velocity is acceleration
so  you integrate the acceleration function to get the velocity

welshfella · Answer

so you need to integrate  =20(1 + 2t)^-2  and plug in the given values of v and t.

mecharv · Answer

Hmmmm 🤔

welshfella · Answer

sorry that's -20(1 + 2t)^-2

welshfella · Answer

can you integrate that?

mecharv · Answer

Definitely. Thanks :)

welshfella · Answer

@samhang?