When people are cold, they often rub their hands together to warm up. How does doing this produce heat? Where does the heat come from?

bacon-cheddar-double-burger meal along with A 65.0-kg mountain climber just ate a Johnny Rocket's two peanut butter milkshakes, which have 5810 Calories (5810 kilocalories). Assume she can convert these calories into energy with 100% efficiency and use the fact that 1 kcal = 4186 J. Calculate how many times she could climb up Mt. Everest - the world's tallest mountain. The height of Mt. Everest is 8840 m.

A 1.5-hp blender spends how much energy in 2 minutes? O 3J 0.75 J O 2,250 J O 135,000 J O None of the choices given.

You are cold, so you cover yourself in a blanket. A half hour later, you feel much warmer. Explain in detail where the heat came from, and how the blanket helped.

Why does air friction affect a car's gas mileage?

The United States Patent and Trademark Office rejects claims for perpetual motion machines (in which energy output is as great or greater than energy input) without even investigating them. Why is this?