Question

A rock thrown with speed 8.50 m/s and launch angle 30.0 ∘ (above the horizontal) travels a horizontal distance of d = 20.0 m before hitting the ground. from what height was the rock thrown? use the value g = 9.800 m/s2 for the free-fall acceleration. a second rock is thrown straight upward with a speed 4.250 m/s . if this rock takes 2.717 s to fall to the ground, from what height h was it released?

Answer 1

KINEMATICS

Uniform or constant motion in a straight line (rectilinear). Speed or velocity constant and/or acceleration constant. If motion is up and down and/or has an up and down component then acceleration omn earth will be g. g is about 10m/s/s.

speed = distance/time

velocity = displacement/time

s=distance ... u=initial speed ... v = final speed ... a = acceleration ... t = time

v=u+at

v^2=u^2+2as

s=ut+1/2at^2