Soaring birds and glider pilots can remain aloft for hours without expending power. How do they do it?

Q: a) Find the change in the mechanical energy (potential + kinetic) of the block from the top to the…

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Q: What is the significance of steam engine?

A: Its a concept of heat engine

Q: A piece of lead is dropped from an aeroplane at a height of 200m. If 60% of the striking energy is…

A:

Q: A small 142 gram (0.142 kg) pinewood derby car sits at the top of a 1.20 meter high sloped…

A: SOlution: Given that m = 0.142 kg h = 1.2 m energy loss = 5% of its energy

Q: A 10-kg box has a potential energy of 2000 J. How high is it suspendedl

A: Given, Mass, m = 10 kg  Potential energy , PE = 2000 J  We know that, Potential energy = mgh…

Q: A 68-kg woman is planning to bicycle for an hour. If she is to meet her entire energy needs while…

A: A 68-kg woman is planning to bicycle for an hour. If she is to meet her entire energy needs while…

Q: Why does the temperature of gas increase when it is suddenly compressed?

A: Temperature of gas increase when it is suddenly compressed because

Q: A 60-kg person proposed to drink a 900-kilocalorie brown-sugar milk tea with pearls and pudding, and…

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Q: Why must a glass dish taken from the oven and put into cold water shatter?

A: A glass dish taken from the oven and put into cold water shatter because When hot, thick glass is…

Q: A hot air balloon with a mass of 700kg ascends at a constant rate of 1.60m/s for 20.0s. How much…

A: Given: The mass of the balloon is 700 kg. The constant speed of the balloon is 1.6 m/s. The time…

Q: A 0.12 kg mass is hung from a string creating a pendulum. It’s raised 8 cm vertically and let go.…

A: Given that:- Mass of object=0.12kg

Q: From what height must a block of ice be dropped so that it melts completely on falling? Assume…

A: The amount of heat per unit mass transferred during change of state of substance is called latent…

Q: Which is the smaller temperature increment - a degree Celsius or a degree Fahrenheit? Explain.

A: You see that Celsius has 100 degrees between the freezing and boiling point, whereas Fahrenheit has…

Q: When an air molecue is hit by an approaching faster moving molecule, does its rebound speed increase…

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Q: Roofs of the huts are blown up during stormy days. Why?

A: Roofs of the huts are blown up during stormy days because

Q: A 100kg steel support rod in a building has a l'ength of 2.0m at a temperature of 20°C. The rod…

A: i. The formula of the extended length of the rod is: Substitute the shown values and solve for the…

Q: Water going over Iguaçu Falls on the border of Argentina andBrazil drops through a height of about…

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Q: Is energy transfer involved in a phase change? If so, will energy have to be supplied to change…

A: Yes, the energy transferred (released or absorbed) is involved in Phase Change also. This energy…

Q: How much energy is converted to heat in braking a 1000 kg car to a speed of 5.00 m/s from an initial…

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Q: If you slide down a rope, it’s possible to create enough thermal energy to burn your hands or your…

A: It is given that,

Q: 119. As a thrown baseball is acted on by air friction, the thermal energy of the ball (1) decreases…

A: Kinetic energy decreases over time as frictional force due to air acts on it.

Q: Discuss the relative effectiveness of dieting and exercise in losing weight, noting that most…

A: To burn the stored fat or to lose weight a person has to follow both dieting and exercise. The…

Q: Radiant energy is proportional to A. T В. Т? C. T D. T

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Q: On a cold windy day, a window will feel colder than on an equally cold day with no wind. This is…

A: Concept: The temperature of two systems is the same when the systems are in thermal equilibrium,…

Q: Supposed that you eat Skyflakes Cracker having a food calorific value of 120kcal and 22% of this…

A: Given  Food calorific value CV=120kcal=120×4184=502080J Useful work W=502080×0.22=110457.6 J Mass…

Q: 24. A hot air balloon with a mass of 700kg ascends at a constant rate of 1.60m/s for 20.0s. How much…

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Q: Rub your hands together vigorously. What happens? Discuss the energy transfers and transformations…

A: Hands are felt warm when rubbed. When we rub the hands,hands are having kinetic energy .It is the…

Q: What is meant by translational kinetic energy?

A: Kinetic energy is the energy possessed by a body by virtue of its motion. A body can have motion by…

Q: The heat never flows spontaneously from a colder object to a hotter object. why?

A: Heat flows

Q: It is possible to melt ice by rubbing one block of it against another. How much work, would you have…

A: Given that the mass of the ice and We have to determine the value of work which is used to get…

Q: A ½ kg ball dropped from a height of 2 m rebounds to only 1.2 m after hitting the ground. The amount…

A: Find the amount of energy converted to heat. ∆E=mg∆h=mgh2-h1

Q: Supposed that you eat Skyflakes Cracker having a food calorific value of 120kcal and 18% of this…

A:

Q: The energy stored in a foot of snow on a steel roof is

A: NOTE: The question must be (on a steep roof) instead of (on a steel roof) To find out which type of…

Q: Your mass is 56 kg and eat 700-calorie food, calculate how high of stairs you must climb to work off…

A: The given values with suitable variables are listed below. Here, m denotes the mass and E denotes…

Q: A gas in a closed container is added with 20J of heat. The lid to the container is then lifted for…

A: Heat energy added to a gas in closed container = 20 J force = 2.5 N lid is lifted by a distance = 20…

Q: Rubbing your hands together warms them by converting work into thermal energy. If a woman rubs her…

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Q: Will the temperature of air rise as it is compressed by an adiabatic compressor? Why?

A: