You are here:

Question

Math 4 Q7
Seventh of nine questions.
I'm using screen shots to ensure you see what I see.
All answers are integers in the range 0 to 9.
Where required, assume g=9.81

Impulse (J) is change in momentum, so you have:

J = m v2 - m v1

The mass m has not changed, and you know v1 and |J| and the direction of v2.

You end up with:

|J|^2 = m^2 |v2|^2 - m^2 |v1|^2

This is because v1 and v2 are perpendicular (they are essentially just the the x- and y-coordinates of J).

This gives |v2| = 33.2465, and thus if you want the angle, you have:

tan(θ) = |v2|/|v1|, giving θ = 1.09812 radians

I suspect they want degrees, and that measure is 62.9179 degrees.

So I suppose "j" is 6-2=4.
Questioner's Rating
 Rating(1-10) Knowledgeability = 10 Clarity of Response = 10 Politeness = 10 Comment No Comment

Volunteer

#### Clyde Oliver

##### Expertise

I can answer all questions up to, and including, graduate level mathematics. I am more likely to prefer questions beyond the level of calculus. I can answer any questions, from basic elementary number theory like how to prove the first three digits of powers of 2 repeat (they do, with period 100, starting at 8), all the way to advanced mathematics like proving Egorov's theorem or finding phase transitions in random networks.

##### Experience

I am a PhD educated mathematician working in research at a major university.

Organizations
AMS

Publications
Various research journals of mathematics. Various talks & presentations (some short, some long), about either interesting classical material or about research work.

Education/Credentials
BA mathematics & physics, PhD mathematics from a top 20 US school.

Awards and Honors
Various honors related to grades, various fellowships & scholarships, awards for contributions to mathematics and education at my schools, etc.

Past/Present Clients
In the past, and as my career progresses, I have worked and continue to work as an educator and mentor to students of varying age levels, skill levels, and educational levels.