Use the table below to identify four substances that undergo a physical change if the temperature is reduced from 50oc to - 50oc. what is the physical change that takes place in each case.

when electrons are excited to differnt energy levels, the average radii from the nucleus also changes. Rank the following electron energy states according to the average distance of the electron from the nucleus.

I push a box with mass 10 kg across a 15 m room. If I apply a force of 20N to do this how much work is being done on the box?

Lance has a moment of inertia of 420 kg m2 while riding the Rotor. The floor of the Rotor drops out from under its riders once it reaches the angular velocity (_ omega) of 1.6 radians per second. Calculate his angular momentum.

In a 3D printer, on the correct spot. is a heated nozzle that melts the material and places it on the correct spot. The warming pen The pull end The extruder The hot end

How much volume (in cm3) is gained by a person who gains 11.4 lbs of pure fat?

Show that the Newton has the units of mass times acceleration.

Light travels at 150000000km from the sun to earth in 8 minutes. What speed is this in Km/s

Electricity problem (coulomb's law)

An observer (O) spots a plane (P) taking off from a local airport and flying at a 29° angle horizontal to her line of sight and located directly above a tower (T). The observer also notices a bird (B) circling directly above her.

In order for convection to occur, you must have