# Search results

1. ### Unable to solve equation

Homework Statement \frac {xy}{x+2y} + \frac {x+2y}{xy} = 2 \frac {xy} {x-2y} + \frac {x-2y} {xy} = 4 The attempt at a solution I tried replacing ( \frac {xy} {x+2y} = p , say and \frac {xy} {x-2y} = q , say is getting nowhere as i can't find a relationship between the...
2. ### Log equations

It doesn't work that way!! log_5 x = (1/2)(log_5 25) log_5 x = (1/2) 2 log_5 x = 1 Please learn the basics and stuff... it will help!
3. ### Problem on conservation of energy/momentum

Thanks doc, you're a lifesaver.... another question I can't seem to grasp... Two particles (mass m1 and m2) are moving on a horizontal plane with speeds v1 and v2. Angle between them is A. What is the total momentum. Won't it just be m1v1 + m2v2cosA? In the book its give as sqrt((m1v1)^2 +...
4. ### Problem on conservation of energy/momentum

Yes but the angle is not give. Could that be a problem?
5. ### Problem on conservation of energy/momentum

About the other problem... original velocity is along x axis so y component is 0. Since after splitting momentum is conseved then along the y axis the momentum of the second particle will cancel out the one of the first particle and will also be along the y axis in the opposite dir...
6. ### Problem on conservation of energy/momentum

Thanks, Doc! I think I've got it... please verify! P.S. This is my first attempt to use LaTeX... forgive if something goes wrong. According to problem, total kinetic energy of the particles is E m_1v_1^2/2 + m_2v_2^2/2 = E Initial momentum = O (system at rest) New momentum = m_1v_1...
7. ### Problem on conservation of energy/momentum

This problem makes more sense: A body (mass M) is moving with velocity Vo. It breaks into two pieces, one of which (mass m) is traveling with speed V1 in the direction perpendicular to Vo. What is the speed of the other piece. Mass of other piece is (M-m). The problem I am finding is I don't...
8. ### Momentum of a boat problem

Read my post #4 and solve accordingly by equating initial and final momentum... there is nothing wrong with the answer, it seems pretty plausible.
9. ### Momentum of a boat problem

Velocity of the package is, as given, 10m/s. It will be part of final momentum. Initial momentum = momentum when the system (boat+boy+package) is at rest Final momentum = momentum at the moment of throwing of package Do you know what the correct answer is?
10. ### Momentum of a boat problem

Let m1 = mass of package m2 = mass of boat+child Initial momentum = Final momentum Initial momentum = 0 = m1v1 = m2v2 Don't take my word for it though, i'm still very new to conservation laws myself...
11. ### Question to find air resistance

Homework Statement A body of mass m is dropped from a certain height without initial velocity. At the time t when its speed is v, what is the work done by the air resistance to retard the body? Homework Equations Laws of conservation of momentum and inertia The Attempt at a Solution...
12. ### Problem on conservation of energy/momentum

There is no original velocity, the particle is at rest. Hmm... thats possible but only is the momentum of the the split particles is equal ... can anyone verify this?
13. ### Problem on conservation of energy/momentum

Homework Statement A particle breaks into two pieces m1 and m2 traveling with velocities v1 and v2 respectively. The total kinetic energy of the particles is E. What is the velocity of each particle? Homework Equations Law of conservation of energy Law of conservation of momentum The...
14. ### Yet another inequality proof

For all real values of x and y prove that x^2+2xy+3y^2+2x+6y+4 >= 1 I am trying to express the left side as a sum of sqares but always come short. Help will be appreciated.
15. ### Another inequality proof

The problem For all a>0 and b>0 if a^3+b^3 = a^5+b^5 prove that a^2+b^2<=1+ab I have no idea on even how to start... i have tried using trigonometry (like in previous post) but come to a dead end... i am looking for the simplest method...
16. ### Inequality Proof

Any other simpler methods?
17. ### Inequality Proof

Sorry I'm quite weak in trigonometry... could you elaborate?
18. ### Inequality Proof

1. The Problem For all positive real values of a,b and c such that a²+b²+c²=1, prove that a(b+c) < [1/sqrt(2)] 2. My Attempt... There are probably numerous ways to solve this, but i tried this way... let a = sin(x) b = cos(x)sin(y) c = cos(x)cos(y) a²+b²+c² =...
19. ### Kinematics Question

But it doesnt hit the plane at its maximum height. Or am I missing something?
20. ### Kinematics Question

Q: A plane is flying horizontal to the ground with uniform velocity Vo. A stone is thrown at it with velocity V1 and angle alpha to the horizontal. If the stone hit the plane, at what height is it flying? The simple equations of uniform acceleration are available to me. We obviously have...
21. ### Body Throw Kinematics Question

I do not know where to start with the problem. I can work with the simple equations of motion s=ut+(at^2)/2 v=u+at
22. ### Body Throw Kinematics Question

A body is thrown up on a slope. It reaches a point (l, say) 2 times: at t1 = 1sec and t2=2sec. What is the initial velocity with which it is thrown Steps and explanation will be helpful Thank u
23. ### Simple Kinematics Question 2

A body starts moving with velocity Vo and constant acceleration a. After moving a certain distance, it attains a velocity of V. What is its velocity as it moves half the distance? Vo = 1m/s V = 7m/s
24. ### Simple Kinematics Question

In the same problem, what is the time taken by the body to attain a velocity twice its initial velocity? What is the displacement of the body at that time?
25. ### Simple Kinematics Question

thanks, all done
26. ### Simple Kinematics Question

g acts in y direction. velocity is constand is x direction. angle of throw, as mentioned, is perpendicular to the ground, and sincs cos90 = 1 it can be neglected. i need help solving it.
27. ### Simple Kinematics Question

A stone (taken as a point mass) is thrown from a cliff of height H = 80m perpendicular to the ground. It falls L = 60m away from the cliff. What is the initial velocity V with which the stone is thrown? Obviously we have to deduce the formula for velocity using kinematic equations w/ respect to...