# Projectile Motion problem

1. Jul 28, 2014

### Vibhor

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

Maximum height attained by first projectile H = u2sin2θ/2g = 15m

If acceleration vector is assumed a = axi+ayj , then at H √(ax2+ay2) = 50 .

Now I need to use the given conditions to come up with another equation . Not sure how to proceed .

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Last edited: Jul 28, 2014
2. Jul 28, 2014

### Staff: Mentor

3. Jul 28, 2014

### Vibhor

Please see if it is viewable now .

4. Jul 28, 2014

### Vibhor

Could somebody help me with the problem .

5. Jul 29, 2014

### Staff: Mentor

Figure out the centripetal acceleration at that point. Hint: Use the fact that the first projectile is at its apex at the point H.

6. Jul 29, 2014

### Vibhor

Hi Doc

Your suggestion has worked nicely .Thanks a lot .

I was just wondering what do we infer from the third line in the problem " such that the speed is increasing continuously ". We didn't make any use of it .

7. Jul 29, 2014

### Staff: Mentor

You make use of that fact in determining the direction of the horizontal acceleration component. It tells you that ax is positive.

8. Jul 29, 2014

### Vibhor

Thank you very much .