# Kinematics Problem involving variable acceleration

1. Jan 27, 2010

### zewei1988

1. The problem statement, all variables and given/known data
What if the acceleration is not constant? A particle starts from the origin with velocity 8 i m/s at t = 0 and moves in the xy plane with a varying acceleration given by vector a = (7√t j) m/s2, where t is in s. Answer the following using t as t as necessary.

Determine the vector velocity of the particle as a function of time.

2. Relevant equations

3. The attempt at a solution

I could find the x-component of the velocity vector, but integrating 8 with respect to time. However, when my answer is wrong when i integrated 7(t^0.5) in an attempt to find the velocity of the particle as a function of time.

4.67t^(1.5) is my answer.

2. Jan 27, 2010

### tiny-tim

Welcome to PF!

Hi zewei1988! Welcome to PF!

(try using the X2 tag just above the Reply box )
What do you mean? The 8i velocity component is constant.

3. Jan 27, 2010

### zewei1988

I'm sorry, I din integrate it with time. I mixed up my solutions for the other part of the question. I simply put 8 as the velocity vector along the x-axis.

4. Jan 27, 2010

### tiny-tim

So your answer is 8i + 4.67t3/2j ?

That looks ok to me.