Why doesn't the principle of mechanical energy conservation hold in situations when friction forces are present?

A car advertisement claims their car can go from a stopped position to moving 60 miles per hour in 5 seconds. The advertisement is describing the car's acceleration. speed. velocity. direction.

Which of the following is a property of all periodic waves? A. They follow a repeating pattern as they propagate. B. They oscillate in a direction perpendicular to the direction in which they propagate. C. They tend to propagate in a circle. D.

What unit is used to measure energy?

Which material is ideal for an office door that allows light to pass through, but maintains privacy? A. clear glass B. wood C. frosted glass D. metal

Jed drops a 18 kg box off of the Eiffel tower. After 6.1 seconds, how fast is the box moving (neglect air resistance.) A. 1100 m/s B. 78 m/s C. 180 m/s D. 3.3 m/s E. 60 m/s

A sample contains 10 g of a radioactive isotope. How much radioactive isotope will remain in the sample after 2 half-lives? A. 7.5 g B. 5.0 g C. 2.5 g D. 10.0 g

A plane flies along a straight line path after taking off, and it ends up 210 km farther east and 90.0 km farther north, relative to where it started. What is the plane's displacement?

Compare exothermic reactions and endothermic reactions. Give at least one similarity and one difference.

A solid cylinder with a radius of 73.3 cm and a mass of 2.33 kg accelerates uniformly from rest in 4.13 seconds while experiencing 6.71 rotations. Solve for the (a) final angular velocity.

In the early stages of its formation, earth became hot enough that some of its solid materials turned to liquid. Which of these factors did not directly contribute to earths high internal temperatures