The density of free electrons in gold is 5.90times 10^28electrons/m^3 Find the drift speed of electrons in a gold wire of diameter 2.98 mm when a current of 0.175 A flows through the wire. 17.8times 10^-6m/s 4.32times 10^-6m/s 15.8times 10^-8m/s 2.65times 10^-6m/s 3.00times 10^8m/s
Newton's laws of motior fail: when dealing with extremely low masses. for objects with extremely large masses. when using atomic clocks rather than stopwatches. at speeds significantly less than the speed of light. in helping us understand most of the everyday world.
A radioactive substance decays exponentially. A scientist begins with 140 milligrams of a radioactive substance. After 24 hours 70 mg of the substance remains. How many milligrams will remain after 27 hours? square mg Give your answer accurate to at least one decimal place Question Help: Video
The branch of biomechanics that deals with the aspects of moving systems is known as dynamics. kinetics. mobility. kinematics.
When a forklift is loaded, where is its center of gravity? A. Under the operator B. At the center of the forklift C. Varies based on the combined centers of gravity of the forklift and the load D. At the center of the forks
Living and Nonliving substances obey all of the answers the 1st law of thermodynamics. the 2nd law of thermodynamics. the law of gravity.
Whose laws of motion became the basic building blocks for our understanding of the functioning of the universe? Johannes Gutenberg Martin Luther Isaac Newton Francis Bacon Rewatch
What happens if supercells form too close to each other? They will cause a derecho That's the plot of Sharknado They merge into a huge supercell Their outflows may interact and they may dissipate
The Universe is thought to be on the order of __ billion years old. 37 3.7 13.7 137 1370
Physics is explicitly involved in studying which of these activities? A. the mixing of metals to form an alloy B. the metabolic functions of a living organism C. the motion of a spacecraft under gravitational influence D. the depletion of the atmospheric ozone layer due to pollutants E. the killing of cancerous cells by radiation therapy
a 4.0 kg object moves at $8.0m/s$ what is its momentum? $32kg\times m/s$ $12kg\times m/s$ $24kg\times m/s$ $48kg\times m/s$
When can you apply the idea that momentum is constant to solve a problem? When the system is not isolated but the time interval when the external forces are exerted is very small When the system is isolated When the external forces are much smaller than the internal forces
What is the formula for momentum? $p=m+v$ $p=m\times v$ $p=m\div v$ $p=v\div m$
What are the two most essential components of any medium, regardless of whether it is liquid or solid, or what type of container is used?
A proton is a subatomic particle carrying a charge equal to but opposite that of an electron. Please select the best answer from the choices provided T F
Problem \#3 A nonuniform horizontal bar of mass 15 kg is supported by two massless wires against gravity. The left wire makes an angle $35^{\circ }$ with the horizontal, and the right wire makes an angle $55^{\circ }$ The bar has a length of 5.0 m The bar is in equilibrium. Find: (a) the tension of the left wire (in N) (1 point); (b) the tension of the right wire (in N) (1 point); (c) the position of the center of mass of the bar (in m), measured from the bar's right end (1 point).
What liquid property is defined as the spontaneous flow of a liquid into a narrow tube or porous material? capillary action surface tension vapor pressure volality
The amount of heat energy absorbed or released is represented using __ change in color change in entropy change in enthalpy change in Gibbs free energy
Longer wavelengths will have __ frequencies, and shorter wavelengths will have __ frequencies. A higher; lower B longer; shorter C lower; higher D shorter; longer
Question 3 of 4 What is quantum mechanics? the unified theory of everything the theory that explains how light behaves under classical physics a method to connect multiple transistors to work in tandem in one circuit the ability to describe the interaction and motion of subatomic particles
