110 Answered Questions for the topic Energy
Dear teacher People say : energy is the ability to do work But then" what is work ?" I asked : they said " work is energy tranfered by force " Bla , they use energy to define work and work to... more
two mass connected by string on a slide... about the work and energy things
There a mass of 4kg and a mass of 5kg connected by an inextensible string passing over a smooth pulley .the mass for 4kg starts from rest and moves up the smooth plane inclined at 30degree to... more
Quick Science Question: Calculating Thermal Energy?
A model rollercoaster car weighs 3 kg. If it reaches 5 meters, how much energy is transformed into thermal energy at that point? I have other values too (it's a multiple part... more
A 45.2kg boulder falls off a mountain that is 255 m tall. What is the kinetic energy of the boulder when it falls off the cliff?
I know the answer might be 0J but I need help explaining how to get the answer
A particle with total energy E in Potential energy region U(x).Motion of the particle is restricted to the region when ? check description
A particle with total energy E in Potential energy region U(x).Motion of the particle is restricted to the region when options are (a) U(x)>E (b) U(x)<E (c) U(x)=0 (d) U(x) < or = E
Car have mass m,its engine delivers power P.what's the minimum time in which car can be accelerated from rest to speed v
A car of mass m has an engine which can deliver power P.The minimum time in which car can be accelerated from rest to a speed v is(a) (mv^2)/2P(b) Pmv^2(c) 2Pmv^2(d) (mv^2)P/2
Find mechanical power?
The blades of a wind mill sweep out a circle of area A.If wind flows with velocity v perpendicular to blades of wind mill and its density is D,then the mechanical power received by wind mill is (a)... more
Find Power ?
A pump is used to pump a liquid of density D continuously through a pipe of cross section area A.If liquid is flowing with speed v,then power of pump is(a) (DAv^2)/3(b) (DAv^2)/2(c) 2DAv^2(d)... more
Physics: What are the following for this system: amplitude, frequency, period, spring constant, max velocity and total energy?
A 27.8 gram mass oscillates on the end of a spring and its motion can be described by: (1.5 )sin (21.4 t ) [here the units are standard, meters and seconds] What are the following for this... more
Physics: amplitude, frequency, period, spring constant, max velocity and total energy
A 27.8 gram mass oscillates on the end of a spring and its motion can be described by: (1.5 )sin (21.4 t ) [here the units are standard, meters and seconds] What are the following for this system:... more
Physics: Thermodynamics (ice)
If a 0.06247 kg ice cube initially at 0.00 C is allowed to melt in a Styrofoam cup holding 0.497 kg of water at 10.0 C , what is the total entropy change for this process?
Physics: Change in internal Energy
2.50 moles of an ideal monatomic gas are compressed from 315,000 Pa to 175,000 Pa at 0.0300 m3. What is the change in internal energy in this isochoric process?
a spring of force constant 200N/m is compressed through a distance of 0.05m calculate the energy stored in the string
I.calculate the energy stored in the string II.if the energy in (I.) above is imparted to a body of mass 0.5kg to set it in motion calculate the speed acquired by the body
How much energy in kilocalories(kcal) would combustion of 0.420 ounces of methane release?
The combustion of 45.0g of methane (natural gas) releases 2498 kJ of heat energy. How much energy in kilocalories(kcal) would combustion of 0.420 ounces of methane release?
Ideal gas, potential energy help
Let us consider an ideal gas in a gravitational field which is uniform with strength g. The gas is trapped in a highly realistic h=10km vertical column of height h with perfectly insulating walls.... more
Physics-Energy/ conservation of energy
Question: At a water park, Hugo climbs a 15.00m springboard, in 22.00s, to execute his famous THUNDER CANNON BALL. Hugo jumps up at 6.000m/s [up] off the end of the diving board and propels his... more
What is the energy transfer of a battery rolling out of a rolling cup?
A cup is on its side. inside the cup is a double A battery. An object hits the cup forcing the cup to roll. As the cup rolls the batter rolls out. What is the energy transfer of the battery rolling... more
Calculate the energy cost (kWh/p/d)
Australia produces 20 megatonnes (Mt) of alumina every year, where each tonne requires 3.8 MWh of heat energy to produce. Calculate the energy cost (kWh/p/d) to produce alumina spread across the... more
The Rydberg Equation and Ionization Energy
I'm not sure where to begin. I really need some help on this one. I have the Rydberg equation here but I have no idea how to use the answer from the equation and use it to find the second... more
How do plants store and use energy?
How do plant cells store energy? Also, how do plant cells use the energy?
Are they any calculation/formula of Ocean Thermal Energy Conversion that uses the unit of power or energy?
example: kWh/d/y, w/m2 etc..
Express your answer in units of kWh/d.
Chickens require 0.075 kWh per day of energy (as feed) for each kilogram of animal, and 2/3 of an adult chicken is edible meat. The lifespan of a chicken is 50 days.What is the daily energy... more
roller coaster energy problem
A roller coaster starts from rest at the top of a hill with 1000J of potential energy. How much kinetic energy does it have? How much total mechanical energy? (KE + PEg + PEs) How much... more
Express your answer as a percentage.
Typical fresh water usage is approximately 150 litres per day per person. If all of this water came from a desalination plant with an energy cost of 4 kWh(e)/m3 what percentage would this be of the... more