PHYSICS ASSIGNMENT A. If a cyclist of mass 70kg uses a bicycle of mass 7kg, how much work must the cyclist do against gravity in order to ascend to 2100m from sea level.

b. One particular descent goes from 2100m to 1600m. Assuming the work done against friction is 90% of the potential energy change of the cyclist and cycle, what Increase in speed in km/h can a rider attain by the end of the descent?

c. What is the average rate of energy conservation of the cyclist and cycle if the descent in part 'b' takes 1 minute at constant speed.

(Acceleration due to gravity, g = 10ms^-2)

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

What quantity do units represent in value