physics
posted by lina .
A man stands on the roof of a 19.0 mtall building and throws a rock with a velocity of magnitude 30.0 m/sat an angle of 42.0 degrees above the horizontal. You can ignore air resistance.
Calculate the maximum height above the roof reached by the rock.
Calculate the magnitude of the velocity of the rock just before it strikes the ground.
Calculate the horizontal distance from the base of the building to the point where the rock strikes the ground.

physics 
drwls
The vertical component of velocity when the rock is thrown is 30 sin 42 = 20.07 m/s
Calculate the time T that it takes the rock to hit the ground using that initial velocity.
Hint: 20.07 T  (g/2) T^2 + 19.0 = 0
I assume you know what g is, and how to solve that quadratic equation. Take the positive root.
T times the horizontal velocity component is the horizontal distance that the rock travels.
The maximum height h of the rock is attained when the vertical velocity component is zero. This happens when
gt = 20.07 m/s
h = (1/2)(20.07 m/s)^2/g
Ebergy considerations can be used to compute the velocity at impact 
physics 
yara
Vo = 30 m/s
Xo = 0
Yo = 0
theta = 42
ax = 0 m/s^2 i
ay = 9.8 m/s^2 j
Vox = 30cos42
Vox = ____ m/s i
Respond to this Question
Similar Questions

Physics
A man stands on the roof of a 19.0 mtall building and throws a rock with a velocity of magnitude 24.0 m/s at an angle of 38.0 degrees above the horizontal. You can ignore air resistance. Calculate the maximum height above the roof … 
Physics
A man stands on the roof of a 19.0 mtall building and throws a rock with a velocity of magnitude 24.0 m/s at an angle of 38.0 degrees above the horizontal. You can ignore air resistance. Calculate the maximum height above the roof … 
physics
A man stands on the roof of a 10.0 tall building and throws a rock with a velocity of magnitude 24.0 at an angle of 42.0 above the horizontal. You can ignore air resistance. Calculate the magnitude of the velocity of the rock just … 
Physics
A man stands on the roof of a 10.0 tall building and throws a rock with a velocity of magnitude 30.0 at an angle of 38.0 above the horizontal. You can ignore air resistance. Calculate the horizontal distance from the base of the building … 
physices
A man stands on the roof of a building of height 13.8 and throws a rock with a velocity of magnitude 29.3 at an angle of 34.8 above the horizontal. You can ignore air resistance 
physics
A man stands on the roof of a 19.0 m tall building and throws a rock with a velocity of magnitude 30.0 m/s at an angle of 30.0 degrees above the horizontal. Ignore air resistance. Calculate the horizontal distance from the base of … 
physics
A man stands on the roof of a 10.0 tall building and throws a rock with a velocity of magnitude 30.0 at an angle of 34.0 above the horizontal. You can ignore air resistance. Calculate the horizontal distance from the base of the building … 
physics
A man stands on the roof of a 10.0 tall building and throws a rock with a velocity of magnitude 30.0 at an angle of 34.0 above the horizontal. You can ignore air resistance. Calculate the horizontal distance from the base of the building … 
science
A man stands on the roof of a building of height 15.8m and throws a rock with a velocity of magnitude 25.2m/s at an angle of 32.7∘ above the horizontal. You can ignore air resistance. Part A Calculate the maximum height above … 
physics
a man stands on the roof of a 15.0m tall building and throws a rock with a velocity of magnitude 30.0m/s at an angle of 33 degrees above the horizontal. ignoring resistance calculate the horizontal distance from the base of the building …