Homework Help: Physics

Posted by Tammy on Wednesday, September 26, 2007 at 1:27pm.

A projectile is shot horizontally at 30m/s from the roof of a building 100m tall. Use g=10m/s^2. Choose + vertical direction to be pwards.
a) determine the time necessary fot the projectile to reach the ground below
b) determine the horizontal distance from the base of teh building that the projectile lands
c) determine the horizontal and vertical components of the velocity just before the projectile hits the ground
d) determine the magnitude of the total velocity just before the projectile hits the ground.

a)would I use y=y_0 +v_0t +1/2 at^2
100=0+0+1/2(-10)t^2 and solve for t? when i did i got 4.47s
b) would i use x=x_0+v_xt
=0+30*4.47
=134.1m
c)for the horizontal componet i believe i use v=v_0 +at and for the vertical: x=x_0+vt
d) v_total =sqrt(vx^2 +vy^2)

Are these equations I came up with correct to solve this problem?

Physics - bobpursley, Wednesday, September 26, 2007 at 1:53pm
a) right equation.
b) right
c) NO. Horizontal velocity remains the same as initial (30m/s). The vertical velocity is -g*timeinair.
d)Right formula.

Answer this Question

Related Questions

Physics - A projectile is shot horizontally at 30m/s from the roof of a building...
Physics - A projectile is shot horizontally at 30m/s from the roof of a building...
Physics - An objectis thrown upward from the edge of a tall building with a ...
Physics - A ball thrown horizontally at 18.3 m/s from the roof of a building ...
Physics - A projectile is fired from ground level with a speed of 40 m/s at an ...
physics - A ball thrown horizontally at 17.0 m/s from the roof of a building ...
Physics - A ball is thrown horizontally from the roof of a building 29.7 m high ...
Physics - How do you find the "range" for a projectile launched where ...
physics - a ball is thrown horizontally -> from the roof of a building 45...
Science - A ball is tossed at 10m/s off the top of a 100m tall building. Find ...

For Further Reading

First Name:
School Subject:
Answer: