Conservation of mechanical energy problem

Thread starter renob
Start date Oct 15, 2008
Tags

Conservation Energy Mechanical Mechanical energy

AI Thread Summary

The problem involves a bird dropping a 2.00 kg fish from an altitude of 5.40 m while flying at 18.0 m/s. To find the speed of the fish upon hitting the water, the conservation of mechanical energy principle is applied, disregarding friction. The initial kinetic energy of the fish is based on its initial speed, while the potential energy is determined by its height. The correct approach involves equating the change in kinetic energy to the change in potential energy. Ultimately, solving for the final speed of the fish requires careful application of these energy principles.

Oct 15, 2008

renob

Homework Statement

A bird is flying with a speed of 18.0 m/s over water when it accidentally drops a 2.00 kg fish. If the altitude of the bird is 5.40 m and friction is disregarded, what is the speed of the fish when it hits the water?

2. The attempt at a solution

I tried v^2= 2(9.8)(5.4) but didn't get the correct answer.

Physics news on Phys.org

Oct 15, 2008

dsptl

use delta KE initial = delta KE final

and solve for V

Oct 15, 2008

renob

nice. thanks

Thread 'Errors and significant figures'

I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...

View full post »

Thread 'A cylinder connected to a hanging mass'

Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...

View full post »

Thread 'Explain this asphalt sheen'

This problem is two parts. The first is to determine what effects are being provided by each of the elements - 1) the window panes; 2) the asphalt surface. My answer to that is The second part of the problem is exactly why you get this affect. And one more spoiler:

View full post »