PLEASE HELP A person throws a 0.21 kg ball straight up into the air. It reaches a height of
10 m. What is the force on the ball as it begins to fall? (The acceleration due
to gravity is 9.81 m/s2)
A. 4.32 N
B. 2.06 N.
C. 1.18 N
D. 4.67 N

Suppose that a comet that was seen in 563 a.d. by chinese astronomers was spotted again in year 1951. assume the time between observations is the period of the comet and take its eccentricity as 0.986. what are (a) the semimajor axis of the comet's orbit and (b) its greatest distance from the sun?

Which type of wave can travel without a medium

Unpolarized light whose intensity is 1.19 w/ is incident on a polarizer. (a) what is the intensity of the light leaving the polarizer? (b) if the analyzer is set at an angle of = 41.0∘ with respect to the polarizer, what is the intensity of the light that reaches the photocell?