There are slightly more than one-hundred elements known to exist. The smallest complete unit of an element that serves as the basic building block of matter is the

A. atom.

B. proton.

C. neutron.

D. nucleus.

A rock weighing 98 newtons is pushed off the edge of a bridge 50 meters above the ground. What was the potential energy of the rock before it began to fall?

Who would most likely be required to work with sodium hydroxide? A: a plumber B: a gardener C: a bricklayer D: a mechanic

A mover pushes a 30.0 kg crate across a wooden floor at a constant speed of 0.75 m/s. If the coefficient of static friction for wood-on-wood is 0.20, what is the normal force exerted by the floor on the crate?

Consider a circuit with a main wire that branches into two other wires. If the current is 10 A in the main wire and 4 A in one of the branches, how much current is in the other branch?

Trevor lifts a 10kg box to the top of a cliff which is 20m high, in half an hour, then drops the box over the cliff. How much power did he use to lift the box?

Which of the following statements best describes the relationship between force and work? a. Work equals force divided by distance. b. Force and work are two terms for the same thing. c. Work is equal to certain forces, like gravity and friction. d.

A herringbone or tire track pattern on a radiograph is a result of

A 7150-kg railroad car travels alone on a level frictionless track with a constant speed of 24.5 m/s. A 3100-kg load, initially at rest, is dropped onto the car What will be the car's new speed?

How is friction related to conservation if mechanical energy?

Does the ear drum vibrates when struck by sound waves and directly sends a message to the brain that is then recognized as sound?