The problem of a rock thrown vertically up

The problem of a rock thrown vertically up

A rock is thrown vertically upward from the ground with an initial speed 15m/s. a. how high does it go b. how much time is required for the rock to reach its maximum height? c. what is the rock’s height at t=2.00s? (Posted by Merhawi) Answer: (a) u=15m/s a=-10m/s2 v=0 m/s (at the max height) S=? v2-u2=2aS S=v2-u2/2a =225/20 =11.25 m (b) From the above case using v=u+at t=v-u/a=1.5s (c) Use S = ut + 1/2 at2 put t=2s, u = 15m/s, a=-10m/s2 S=30 – 20 = 10 m (If…

Read More

A numerical from Projectile motion, friction and more

A numerical from Projectile motion, friction and more

Hale asked: One side of the roof of a building slopes up at 33.5°. A roofer kicks a round, flat rock that has been thrown onto the roof by a neighborhood child. The rock slides straight up the incline with an initial speed of 15.0 m/s. The coefficient of kinetic friction between the rock and the roof is 0.430. The rock slides 10.0 m up the roof to its peak. It crosses the ridge and goes into free fall, following a parabolic trajectory above the far side of the roof,…

Read More