Recent content by Alex_Neof

For a biconvex lens: R1 > 0 and R2 < 0 (Radius of curvature) not the focal lengths... :confused:

Sorry, I figured it out... both are biconvex lenses therefore their focal lengths are positive. I believe I got confused with radius' of curvatures.. the solution given is the correct one.

Homework Statement A biconvex lens, L_1, with focal length of magnitude \left| f_1 \right| = 15 cm is used with a second biconvex lens, L_2, with focal length of magnitude \left| f_2 \right| = 25 cm to form a compound lens system. If the two lenses are placed in mutual contact what is...

Oh thank you guys for your replies. Zondrina, the problem I am having is determining the limits for Z.

Hi there SteamKing. I will use the Jacobian when I evaluate the integral. ## \int_{r_1}^{r_2} \int_{\theta_1}^{\theta_2} \int_{z_1}^{z_2} r \ dz d{\theta} dr ## something like that.

Homework Statement Using a suitable Jacobian, evaluate the volume bounded by the surface ##z = 2 +x^2##, the cylinder ##x^2 + y^2 = a^2## (where ##a## is a constant), and the ##x-y## plane. Homework Equations ##x = r cos{\theta} ## ##y = r sin{\theta} ## The Attempt at a Solution I...

It is correct, thank you :smile:. I used an online calculator to verify it. I'll write out a solution for any future viewers.

Homework Statement A lamina is bounded by the x-axis, the y-axis, and the curve ##y = 4 -x^2.## Determine the centroid position ##(\bar{x},\bar{y})## of the lamina. Homework Equations ## A = \int_a^b (f(x) - g(x)) dx ## (Area) ##\bar{x} = \frac{1}{A}\int_a^b x(f(x) - g(x)) dx ## ##\bar{y}...

ahaha !. The :wideeyed: is making me laugh. Yeah the question didn't give the units for y. Thanks TSny.

Homework Statement A wave traveling along a long string has the form: ##y(x,t) = 20sin(3x - 2t), ## where ##x## is in metres and ##t## is in seconds. Find the amplitude of the velocity of any particle of the string. 2. Homework Equations Do I just find ##\frac {\partial y}{\partial t}...

Thanks again Suraj. Kind regards and all the best!

So the bob will 'feel' a force of 3mg downwards. Adding this to its weight mg will result in the tension being 4mg upwards.

sorry, since the rocket is accelerating upwards at 3g, does that mean the clock inside is also accelerating upwards at 3g?

Oh, the T is the tension of the string, which is upwards. How would I go about this? It's true I would rather know the method so I can apply the method again in the future.

Thank you !