A certain rain cloud at an altitude of 1.75 km contains 3.20 x107 kg of water vapor.  How long would it take for a 2.70 kiloWatt (kW) pump to raise the same amount of water from Earth’s surface to the cloud’s position?  Give your answer in Earth years. the unit is years.

How much energy would you consume daily if you kept 3 lightbulbs of 25 watts on all day long?.

A swimming pool is 20 m long and 10 m wide, with a bottom that slopes uniformly from a depth of 1 m at one end to a depth of 2 m at the other end (as shown). Assuming the pool is full, how much work is required to pump the water to a level 0.2 m above the top of the pool?

Every so often, someone claims to have built a machine that can generate energy perpetually from nothing. Why isn't this possible according to the known laws of nature? Why do you think claims of perpetual motion machines sometimes receive substantial media attention?

An asteroid made out of iron (7860 kg/m3) strikes the Earth in an areawhere the oceans are very deep. The velocity of the asteroid upon impact isthe same for most debris hitting the Earth’s atmosphere, 30 km/s.The difference in potential energy from orbit to ground is negligible at thisspeed. Assuming that 80% of the asteroid’s kinetic energy is transferred toheating the water, what volume of water (assuming a density of 1000 kg/m3)will be vaporized? We will assume that the water is taken from 70o F tothe point that it becomes steam. Also, assume that the asteriod is spherical,with a radius of 750 m.

Please answer within 90 minutes.

A rubber band at temperature T is fastened at one end to a peg, and supports from its other end a mass m in a gravitational field g. Model the rubber band as a linked polymer chain of N segments joined end-to-end. Each segment has a length a and can be oriented either parallel or anti-parallel to the vertical direction. Find an expression for the average length of the rubber band as a function of B, m, g, N, and a. You may neglect the kinetic energies and masses of the segments themselves, and any interaction between the segments.

If I add 38,626 J of energy to an ideal gas inside a balloon, causing the internal energy to increase by 6,997 J, how much work is done on the environment by the gas as the balloon expands?

The metabolic power for typing is 150 W for Lili, not a lot as you know probably. How long does it take to burn off the energy in a slice of apple pie, which energy content is 1680 kJ (400 food calorie), in minutes?  (Try to stay active, working/studying in front of a computer is not the best exercise you can do for your body.) Your answer needs to have 3 significant figures, including the negative sign in your answer if needed. Do not include the positive sign if the answer is positive. No unit is needed in your answer, it is already given in the question statement.

Q20:  Dr. Fahrrad has been riding his bike to his job and is curious  how many ATP his body is breaking apart in order to do the work required to get to his job. Dr. Fahrrad rides 8.6 kilometers to his job, has a mass of 68.4 kilograms and has an average acceleration of 2.4 kilometers per second squared.  The molecule ATP is able to do work, measured in kilojoules per mole of ATP broken into ADP. The SI unit for work is a joule. Using the information given we can calculate work and then convert to moles of ATP. The first step is to take stock of what we are given in the word problem and what we are trying to find. We have mass, distance, and average acceleration. We are trying to find how many ATP are required to power the bike ride to work. The equation for work, is force times distance and will tell us how many joules Dr. Farrhad is using on his bike ride. It also incorporates one of our given variables, distance. However, the distance was reported in kilometers and the SI unit of…