Ypu. org/physics-motion
practice problems
date:
work each of the following problems. show all work.
3. twins bo and joe have a combined mass of 200 kg and are zooming along at 10
ombined mass of 200 kg and are zooming along at 10 m/s in a 100 kg amusement
car. they bump into melinda's car, which is sitting still. melinda has a mass of 25 kg and is also
in a 100 kg car. after the collision, the twins continue moving with a speed of 4.12 m
a. what is the initial momentum of the system?
nitial momentum is zero
b. what must be the final momentum of the system?
c, how fast is melinda's car bumped across the floor?

Act has a 1200: 5 or 240: 1 turns ratio. it is short circuited. what is the maximum current at 1200a primary if we put a 100ohm resistor across the secondary end of the ct. use it as current source circuit.

Unpolarized light of intensity i_0=750w/m^2 is incident upon two polarizers. after passing through both polarizers the intensity is i_2=280w/m^2. (a) what is the intensity of the light after it passes through the first polarizer in w/m^2? (b) write an equation for the angle between the polarizers in terms of the initial (i_0) and final (i_2) intensities. (c) find the angle between the polarizers in degrees.

While studying chemical reactions and conservation of matter, sarah's class conducted a variety of experiments. sarah and her lab partner found the mass of a wax candle and placed the candle in a flask. the students lit the candle and let it burn to completion. all that was left was wax and charred candle wick. per their teacher's instructions, the students found the mass of the products. their data can be seen in the data table. formulate a hypothesis the students could test to explain why the experiment did not support the law of conservation of matter. a) the students could repeat the experiment using different candles; there might have been a flaw in the candle. b) the experiment should be repeatable. the students should run several trials and then take an average of the after mass in each trial. c) the students should have someone in the class check their measurement skills as they repeat the experiment. they may have made an error using the balance. d) the students should burn the candle in a container that has some type of lid so that any gas that is a product of the reaction can be contained and massed. submit