How are electromagnets different from regular magnets?

They can be turned on and off.

Their polarity can be reversed.

Their strength can be changed.

All of the above.

None of the above.

If an object has a lot of momentum, what statement best characterizes the object?

A person drives 4 miles east and the. 3 miles west

You are building a canoe, and you want to make it out of metal. which property would be most important to consider in choosing which metal to use?

The end of the motor shaft on a router is threaded to accept a a. chuck. c. collet. b. driver. d. clamping nut.

You are standing on perfectly slippery ice. You have a tennis racket and a backpack full of tennis balls, and you propel yourself southward by hitting the tennis balls northward against a brick wall.

The index of refraction of silicate flint glass for red light is 1.620 and for violet light is 1.660. A beam of white light in this glass strikes the glass-air interface at a 25.50∘ angle of incidence and refracts out into the air.

The locations of the major pressure and wind systems on the earth:

Which statements correctly describe the properties of heat? Select all that apply. Heat is an essential component of life on Earth. Heat is energy that flows from one object to another. Heat flows from a hotter object to a colder one.

A book is sitting on a table at rest. Which of the following best describes the forces acting on the book? A.

When NASA's Skylab reentered the Earth's atmosphere on July 11, 1979, it broke into a myriad of pieces. One of the largest fragments was a 1770-kg lead-lined film vault, and it landed with an estimated speed of 120 m/s.?