A helicopter and a jet airplane must work against gravity in order to fly. Which one flys faster

What type of energy increases when friction does work on an object

A steel railroad track has a length of 40 m when the temperature is - 5 ◦C. What is the increase in the length of the rail on a hot day when the temperature is 35 ◦C? The linear expansion coefficient of steel is 11 * 10-6 (◦C) - 1.

A carte with a mass of 155 kg sitting on a flatbed truck which is moving at an acceleration of a = 2.78 m/s2. Suppose that the crate does not slip as the truck undergoes a displacement, whose magnitude is r = 111 m.

the brakes on a car do 240000j of work in stopping the car. if the car travels a distance of 40m while the brakes re being applied. how large is the average force that the brakes exert the car?

Imagine that you were given a ship equipped with a device that could measure how deep the water is. You are asked to use this ship to find a subduction zone. What would you look for as you sailed around the world's oceans?

Which of the following statements does not describe the structure of an atom? a. An atom has a small, dense center called the nucleus. b. Inside the nucleus of an atom are protons and electrons. c. Protons are positively charged sub-atomic particles.

A. Which skill related fitness component is your strongest and weakest?

A 100 N box is placed on an inclined plane that makes a 30° angle with the horizontal. Calculate the component of gravitational force that acts down the inclined plane. A. 25 N B. 50 N C. 87 N D. 100 N

Approximately how many kelvins are equal to 60 c? a. 289k b. 323k c. 333k d. 413k

What are two ways to change velocity?