Recent content by OJones

OK, so you have the time taken to reach maximum height. In that case, the TOTAL time of the trajectory (c) is the time taken to go up AND come back down. It should be apparent that no actual calculation is really required here, but if the solution is not obvious, just do a second calculation as...

If I may, I shall take a moment to respond to the question posed by the OP rather than getting embroiled in arguments about the nature of Type I and II superconductors and diamagnetism. In fact, the original question is significantly simpler to answer, as I understand it. The 'hovering'...

I believe the book in question ('Hyperspace') is indeed on string theory, and was written by Michio Kaku. I have read it myself - an engaging popular account of frontier physics.

So the force of 80N is applied at 1.2m from the axis of rotation, correct? For your calculation of Torque/m.o.i., you have used T=80N. Numerically, are you sure about that? Dimensionally, are you sure about that? Look again...

For the conversion you require, you need to know the atomic mass of Argon from the periodic table. Given this, the answer comes directly from the definition of the mole. Edit: sorry, just realized you already have the atomic mass. In that case, you know that 1mol has mass 39.9g as you say.

The crucial point is that the system is on Earth, i.e. the acceleration of the body is the acceleration due to gravity, which has a given value anywhere on our planet (at least to 4 or 5 sig. fig.). Use this value, which your mechanics teacher should have covered. As for v, well, what is the...

berkeman has it quite correct. Look at the relationship between force and rate of change of velocity (acceleration). P.S. strictly this should be rate of change of momentum, but I won't confuse the issue ;-) Edit: also, are you sure that the 1-2 second interval has the highest slope...

In fact, assuming the system is on Earth, you need very few given variables to answer these mechanics problems. In your case, you have u, a and v. This allows you to apply the fourth equation in your list to find the height reached. From there, work through the other parts of the problem...

It seems that the question is stated in terms of the intensity of light on the surface (a constant 10W/(m^2) - note that this is INTENSITY, not power). In this case there is no need to calculate the intensity of light falling on the surface from the power of the source - it is given in the...