Posted by Anna on Tuesday, March 26, 2013 at 1:58pm.
Here is one of my questions from my physics study. It tells me the answer (35 J), but how do I find that answer? I would appreciate a formula or step by step calculation. Thanks! :)
A 30 kg kid on rollerskates is moving 1 m/s. His brother pushes him with a force of 5 N. What will be his kinetic energy after his brother pushes him 4.0 m? (35 J)
PHYSICS - formula? - Steve, Tuesday, March 26, 2013 at 2:44pm
What acceleration does the pushing impart?
a = 1/6
How long does it take to go 4m, starting at 1m/s?
s = Vo t + 1/2 at^2
4 = t + 1/2 * 1/6 t^2
t^2 + 12t - 48 = 0
t = 4
What's the speed after 4 seconds?
v = Vo+at
= 1 + 1/6 * 4
What's the KE then?
KE = 1/2 mv^2
= 1/2 (30)(5/3)^2
Hmmm. better check my math.
Answer This Question
More Related Questions
- PHYSICS - Here is one of my questions from my physics study. It tells me the ...
- TRIGONOMETRY - Can someone please show me step by step solutions? I'd appreciate...
- Chemistry - Hi Please help verify my answer to the following question: 0.500g of...
- chem - ok my professor lost me when explaining this material so please bare with...
- Physics PLEASE - I'm trying to derive the formula v^2 = v0^2 + 2a(x-x0) were ...
- math - please - How do we manually calculate the Present Value of annuity step ...
- Physics - Hello recently I was asked to find the time it takes a satalite that ...
- precalculus - Find Pk + 1 if Pk = 7 + 13 + 19 + ...+[6(k - 1)+1] + (6k + 1) 7 + ...
- Physics - An arrow is shot straight up from the edge of a cliff with an initial ...
- Chem Check Please!!! - Boric acid, H3 BO3, is a triprotic acid that dissociates ...