What is the efficiency of a device that takes 400J of heat and does 120J of work while giving off 280 J of heat

The floor of a railroad flatcar is loaded with loose crates having a coefficient of static friction of 0.250 with the floor. If the train is initially moving to the right at a speed of 48.

In a single replacement reaction, what will a metal always replace? A metalloid B nonmetal C metal

The two blocks a and b have a mass of 5 kg and 10 kg, respectively. if the pulley can be treated as a disk of mass 3 kg and radius 0.15 m, determine the acceleration of block a. neglect the mass of the cord and any slipping on the pulley.

What is the kinetic energy of a 1kg ball that moves at 5m/s

Isotopes of elements have different: A.) atomic masses B.) atomic numbers C.) electron shells D.) numbers of protons

Crystallization is a separation technique used to produce rock candy from a sugar solution. true or false

A car traveling in a straight line has a velocity of 3.79 m/s at some instant. After 5.4 s, its velocity is 11.9 m/s. What is its average acceleration in this time interval? Answer in units of m/s 2

The periodic law states that elements that have similar properties appear ... a. to the left of each other b. to the right of each other c. at every 10th element d. at regular intervals

An expert archer tried to shoot an arrow into a target lying at the bottom of a shallow pool. Even though the water did not change the direction of the arrow, the archer missed the mark by several inches.

Which of the following best describes a mechanical wave? A. A periodic disturbance of a medium. B. A movement of matter. c. A transfer of energy. D. When energy is converted from one form to another.