Recent content by Legerity

Homework Statement To protect their young in the nest, peregrine falcons will fly into birds of prey (such as ravens) at high speed. In one such episode, a 600g falcon flying at 20.0m/s hit a 1.40kg raven flying at 8.0m/s. The falcon hit the raven at right angles to its original path and...

The 1.38 x 10^-6 answer somehow is right because I inputted it into my online homework, and it said it was the correct answer! And using your method, my calculator always spits out 40000 km/h for the velocity, and I guess it is rounding a lot for that to happen?

I guessed that my calc was giving me 0 because of that too! And about the opposite directions, I am not sure since it is not stated in the original problem at all. I did solve the problem though. I did (372 x 37000)/(10^13) = 1.38 x 10^-6 and that seemed to work. I do not know why though...

Homework Statement In July 2005, NASA's "Deep Impact" mission crashed a 372-kg probe directly onto the surface of the comet Tempel 1, hitting the surface at 37000 km/h. The original speed of the comet at that time was about 40000 km/h, and its mass was estimated to be in the range (0.10-2.5)...

Yes, that is correct.

Yes, there is another part of the question I am stuck on. It is now asking me to find the work done by the frictional force, and my attempts at the problem have been futile. The only things changed in the info in the original post is that now V2 = 2.3 m/s, and time = 8.3 s. Could you possibly help?

The energy will change during the motion, but once it comes to stop, it will be the same as where it started. Work done by gravity on the object (-ΔPE) is needed to move the object. Without a force, there is no work, and without those two the object will be unable to move.

I figured out the problem, and it is the work done by gravity on the box (ΔPE).

I do not think energy transformation is work, but if a force acts upon an object work is involved. I am kind of confused on what exactly you are confused on. Mind being a bit more clearer?

You did not post in the wrong forum, its just that you simply didn't use the HW post layout shown to you when creating a new thread. Initially at rest, the object should have PE = 0 and have a KE, but once something breaks the gravitational force of the Earth, then it gains a PE. Also, if...

You have to use the post layout or else you are going against the guidelines of this section of the forum, but at rest PE = 0 and KE = something, but once motion starts to increase PE increases and KE decreases. This peaks when KE = 0 then object in motion starts to slow down and then reverses...

While an object is accelerating, what is its net force equal to? (In variable terms) Also, for your problem is the human accelerating at a constant rate or not? This should help guide you to your answer.

Homework Statement A 700 kg crate is on a rough surface inclined at 30°. A constant external force P = 5600 N is applied horizontally to the crate. The force pushes the crate a distance of 3.0 m up the incline, in a time interval of 7.3 s, and the velocity changes from v1 = 1.4 m/s to v2 = 2.5...

My mistake I fixed it and got the correct answer! Thank you for all your help!

Using that I got ##65.1 = 900.67 + W_f## ##W_f = -835.57 J## I am still doing something wrong... I found ##W_P## by doing this: $$W_P = 130\cos 30\times 8 = 900.67 J$$