Recent content by k0k

Um, the kinetic energy is at it's maximum when it's approaching the nuclues? Wait.. so is the kinetic energy given to me, is the Ek at the beginning I believe. Not sure how that'll help me though.

Homework Equations a=F/m Ek= 1/2mv^2 --- Not exactly sure how to go through with this.. I tried finding velocity with the given kinetic energy, but am unsure what to do next.

EDIT: Nevermind. My mistake. Read the question wrong, and didn't notice the word "scale". Haha

Weight is the product of both mass and gravity. Thus the reason why it's in Newtons. Acceleration of gravity is 9.81 m/s^2. Therefore.. your weight while free falling would be: W (Weight) = m (mass) X g (gravity) W = 0.12kg X 9.81 m/s^2 W = 1.1772 N

Oh, my bad, a silly error. I got it now. Thanks for the tip on sound making a round trip. : )

A submarine sonar system sends a burst of sound with a frequency of 325Hz. The sound wave bounces off an underwater rock face and returns to the submarine in 8.50s. If the wavelength of the sound is 4.71m, how far away is the rock face? (Ans: 6.51km ) -- v=fλ λ=wavelength f=frequency...

OH, okay got it now. : D Thanks

A 1250-kg race car accelerates uniformly from rest to 30.0m/s in 4.00s on a horizontal surface with no friction. What must be the average power output of its motor? (Ans:141kW) -- P=E/t F=ma Ek=1/2mv^2 -- P=E/t P=Ek/t =(.5X1250kgX15.0m/s^2) / (4.00s) =35156.25 W How...

I end up getting 20588.4J instead. : / -- NEVERMIND. I GOT IT. : ) Thanks

Okay, I am using the law of conversation of energy. I first look for the total energy from the beginning of the platform using: Em= Ep+Ek Em=(mgh)+(mv^2 X .5 ) Em= (56.0kg)(-9.81m/s^2)(15.0m)+ (56.0kg)(21.0m/s^2)(0.5) Em= 4107.6J Then, I calculate the highest point but since the kinetic...

Okay, how does that help me for question a. though?. How do I set up the equation after figuring out the components?. (Please bear with me, I'm kinda slow at this.. : / )

Sorry, but I still don't understand. : / How exactly do I start off? What values do I use to calculate mechanical energy then Potential?.. What about the angle given?..

A human "cannon ball" in the circus is shot at a speed of 21.0 m/s at an angle of 20 degrees above the horizontal from a platform that is 15.0m above the ground. a. If the acrobat has a mass of 56.0 kg, what is his gravitational potential energy relative to the ground when he is at the...