1)A 75 kg cyclist races around a circular track at a constantspeed of 20 m/s. The radius of the track is 50 m. Express both ofyour answers to the nearest whole number.
a) What is the acceleration of the cyclist?
b) What is the net force acting on the cyclist?
2)In the Bohr model ofthe hydrogen atom, an electron circles a proton in an orbit whoseradius is 5.30 x 10-11 m.
a) Find the magnitudeof the gravitational force between the electron and the proton
b) Find the magnitudeof the electrostatic force between the electron and the proton.
For both, express youranswer in scientific notation, rounded to the nearest tenth.
3)Strictly speaking,Newton's law of universal gravitation, F =Gm1m2/r2, is valid only if themasses are either point masses or __________________.
