SOLUTION: <a href='http://postimage.org/' target='_blank'><img src='http://s28.postimg.org/k8oe5odx9/dddds.jpg' border='0' alt="dddds" /></a> I want to know ho to solve these 3 questions

Algebra ->  Numeric Fractions Calculators, Lesson and Practice -> SOLUTION: <a href='http://postimage.org/' target='_blank'><img src='http://s28.postimg.org/k8oe5odx9/dddds.jpg' border='0' alt="dddds" /></a> I want to know ho to solve these 3 questions       Log On


   



Question 856062: dddds
I want to know ho to solve these 3 questions please
thank you .

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
These are not algebra problems but rather physics problems.
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Q47: Gravity acts downwards. Resolve the force into components along the plane and normal to the plane. Along the plane,
a=g%2Acos%2860%29=9.8%2Acos%2860%29=9.8%2A0.5=4.9m%2Fs%5E2
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Q42:Look at the work done by the friction force. It equals the initial kinetic energy of the object.
mu%2AN%2Ad=%281%2F2%29mv%5E2
mu%2Amg%2Ad=%281%2F2%29mv%5E2
mu=v%5E2%2F%282gd%29
mu=8%5E2%2F%282%289.8%29%2810.2%29%29
mu=0.32
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Q49: Since there is a friction force, set up a force balance down the plane.
mg%2Acos%2860%29-mu%2AN=ma
2%289.8%29%280.5%29-3.8=2a
2a=9.8-3.8
2a=6
a=3m%2Fs%5E2