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

Newtons view of arrangement of the universe. don't copy from anywhere.

An electromagnetic wave with frequency 65.0 hz travels in aninsulating magnetic material that has dielectric constant 3.64 andrelative permeability 5.18 at this frequency. the electric fieldhas amplitude 7.20 \times 10^{ - 3} {\rm v}/{\rm m}. a. what is the speed of propagation of the wave? b.what is the wavelength of the wave? c.what is the amplitude of the magnetic field? d.what is the intensity of the wave?

A15 ohm resistor and a 25 ohm resistor are connected in a series to a 60 volt battery. what is the power used by each device