Joules Definition and 123 Threads

Homework Statement A steam iron draws 8.0 A when connected to a potential difference of 120 V. (a) What is the power rating of this iron? 960 W <<<<correct (b) How many joules of energy are produced in 20.0 min? 320 J <<<incorrect why? (c) How much does it cost to run the iron for...

Homework Statement Capacitors A and B are identical. Capacitor A is charged so it stores 4J of energy and capacitor B is uncharged. The capacitors are then connected in parallel. The total stored energy in the capacitors is now ____.Homework Equations U = q^2/2C The Attempt at a Solution Ok...

An ice cube is placed in a microwave oven. Suppose the oven delivers 104 W of power to the ice cube and that it takes 32165 J to melt it. How long does it take for the ice cube to melt? Following my lecture notes and my textbook ... the formula should be t=(J/W), but that isn't giving me...

Homework Statement (a) What is the electric potential energy in joules of two electrons separated by 2.43 nm? (b) What would be it be if the separation was doubled? Homework Equations i think v=kq/r The Attempt at a Solution (a) 1.185 J (b) 0.95 J i can't figure out what I...

Hi there, I am the administrator for an airsoft group based out of the Chicagoland area. Many of our members currently use mesh safety goggles of the sort used in arboriculture, wood chipping, and concrete cutting. These goggles do not have a specific impact rating (though the manufacturer...

So here I am at work, and the go-to people for physics are away. Here is the problem I am trying to figure out: I'm wondering how much energy it takes to compress a certain amount of air at a certain temperature, to a certain pressure. For example, let's say I had a 4-gallon tank of STP air...

how do i convert kJ to joules since that's the standard unit how do i convert mA to amperes how do i convert MV to volts

I'm supposed to determine if a bunch of materials have a high or low impact strength. I did the hard part and determined that the impact strength for each material, but I don't know a relative scale. What is a high value on the izod impact scale test(it's measured in joules). Any idea?

This is an A.P Physics class which is algebra based and does not use calculus. This problem is really annoying because it is one of the easier questions from the homework but i can't seem to understand the procedure. One kilowatt x hour (kWh) is the amount of work or energy generated when one...

How many joules of electric energy are there in 1 kilowatt-hour?

Is 40,000 joules of energy enough for Nuclear fusion?

So Hi, how you transfer from MeV to Joules? Thx, Exam this Friday :)

Suppose you want to heat 40 KG of water by 20 degrees C How many joules of heat are required. Can someone talk me through this step by step?

Please Help... Given: A person walks about 3.6 calories/minute. How much energy is in a 40 Watt light bulb, that is lit for 5.6 hours? Answer: I think it is 144000 J/hr. I am not sure what to do with the 5.6 hours. I think it should be used to caluculate the total J which would be...

pound of tnt = ? Joules Does anyone know what the equivalency is? I tried to google but I get a bunch of star trek websites for some reason...

I have the answer to this question but I am not exactly sure how I got it. Can you explain this to me and show me how to work it. a. When ultraviolet photons from the sun with a wavelength of 292 nm shine onto our skin they provide enough energy to break bonds in our DNA; this can result...

okay I'm having a total brain freeze right now,guess it's because of all the finals I'm studying for. Anyways...I need help converting kcal to joules. Very easy I know...but I'm dumbfounded right now. I have 14.4 kcal and I need to have joules...so do I divide or multiply by 4186 J? Thanks...

Hey I am in need of some assistance. In a problem I need to transfer Joules to quanta but am unsure on how to do it. A radio station is going at 200 KW with a frequency of 103.7 MhZ. So 200,000 Joules a second need to be converted to quanta. Thanks in advance!

how do u convert eV to joules again?

Just to clarify. A particle with a mass of 6 MeV has energy in Joules of 6c^2? And a particle with an energy of 3 MeV has a mass of 3/c^2 kg? And is there a way to convert this energy to a particle's charge?

Is it possible to have a negative joule?

A pump is to lift 16.0 kg of water per minute through a height of 3.38 m. What output rating (watts) should the pump motor have? Potential Energy Initial = O Kenetic Energy Final = 0 So, KE-PE = W 1/2mv^2 - mgh = Work 1/2(16.0)(3.38)^2 - (16.0)(9.8)(3.38) = -439 W The fact that my...

So, first day of school today, and I'm in honors chemistry. I got a packet with refernce tables etc. and a homework assignment designed just to get you to use the tables and be able to connect one thing they say with another. Anyway, one question is "How much heat is required to melt 1g of ice?"...