When conducting objects (such as metals) are connected for a brief time, charge can be made to flow quite easily from one to the other, even if the objects are in contact for an extremely brief amount of time. To that end, consider two identical metallic ball bearings (i. e., two very tiny metallic solid spheres) having unknown charges 41 and 42. It is found that when they are placed 1 m apart, they experience a 25-N attractive force. (a) What can you conclude about the charges on these metal marbles from the information given?
(b) The ball bearings are made to touch very briefly and then are separated by 1 m again. What can you conclude about the charges now? Explain.
(c) Suppose that when the charges are 1 m apart, after briefly touching, they again feel a force of 25 N Determine the charges 41 and 42.

(a) if the pressure in gas is doubled while its volume is held constant, by what factor do (i) vrms and (ii) change? (b) is it possible to boil water at room temperature (20oc) without heating it? explain.

Amass m = 74 kg slides on a frictionless track that has a drop, followed by a loop-the-loop with radius r = 18.4 m and finally a flat straight section at the same height as the center of the loop (18.4 m off the ground). since the mass would not make it around the loop if released from the height of the top of the loop (do you know why? ) it must be released above the top of the loop-the-loop height. (assume the mass never leaves the smooth track at any point on its path.) 1. what is the minimum speed the block must have at the top of the loop to make it around the loop-the-loop without leaving the track? 2. what height above the ground must the mass begin to make it around the loop-the-loop? 3. if the mass has just enough speed to make it around the loop without leaving the track, what will its speed be at the bottom of the loop? 4. if the mass has just enough speed to make it around the loop without leaving the track, what is its speed at the final flat level (18.4 m off the ground)? 5. now a spring with spring constant k = 15600 n/m is used on the final flat surface to stop the mass. how far does the spring compress?

Which of the following statements are evidence that gases do not always behave ideally? check all that apply.? a. co2 gas becomes dry ice (solid co2) at 1 atm and –78.5 °c. b. when two gases are mixed, they follow dalton\'s law of partial pressures. c. at 4 k and 1 atm, helium is a liquid. d. it is impossible to compress a gas enough so that it takes up no volume.