Assume that 10 J/cm2 of the energy in sunlight can damage the human retina. The fovea is a small pit in the retina where vision is the sharpest. If the fovea has an area of 0.018 cm2, how many joules of the Sun’s energy would damage it?

You install solar power in your home, and the solar panel costs $500 and is capable of producing 3 Million joules of energy each day. If electrical costs are $0.15/kilowatt hour, a kilowatt is equal to 1000 watts, and there are 3600 joules in 1 watt hour, how long will it take for the solar panel to pay for itself in electrical savings?

Google Maps A submarine sends a sonar signal, which returns from another ship 7 seconds later. How far away is the other ship if the speed of sound in seawater is 1,530 meters/second? Next

A metal has a density of 8.5 g/cc. What will be the volume of one kilogram of the metal?

Iron is melted during the recycling process. (a) How much heat must be transferred to each kilogram of iron to bring it to its melting point, 1,536°C, from room temperature, 20°C?_________ J(b) About how many cups of coffee could you make with this much energy (1 cup = 73,600 J)? __________cups

A hot-air balloon has a volume of 2,387 m3. The density of the air outside the balloon is 1.176 kg/m³, and the density of the hot air inside is 0.887 kg/m³. How much weight can the balloon lift?

As part of an exercise program, a woman walks south at a speed of 2.8 m/s for 46 minutes. She then turns around and walks north a distance 3,986 m in 50 minutes . What is the woman's average speed in m/s during her entire motion?

The recommended daily caloric intake is 2000 calories (8,400,000J). This is because this is the same value for how much the average body loses to heat and work in a typical day (your change in energy is zero because you take in the same amount of energy you lose).  A) If you lose a total of 8,400,000J (Qout+W=total lost), but consume 1200 calories of food (5,000,000J), what would your change in energy be? B) Assuming your change in energy is negative (hint-it should be), where does your body get the extra energy to maintain it's temperature?

Covid Bryant built an electronic measuring device that depends on determining how long it takes light to travel from the device to a target and back to the device. If Covid Bryant's device indicates that it takes 0.0001056 seconds for light to travel from device to target to device, what is the distance between the device and the target in feet? Assume that the speed of light is 186,218 miles per second for existing atmospheric conditions.

A 0.003 kg piece of copper is heated and fashioned into a bracelet. The amount of energy transferred by heat to the copper is 66,300 J. If the specific heat of copper is 387 J/kg °C, what Is the change of the copper's temperature?