Posted by **Anonymous** on Friday, February 4, 2011 at 4:37pm.

A cannonball is fired horizontally from the top of a cliff. The cannon is at height = 70.0 above ground level, and the ball is fired with initial horizontal speed . Assume acceleration due to gravity to be = 9.80 .

- physics -
**Damon**, Friday, February 4, 2011 at 5:11pm
Well, you did not say what the question is but you have two problems, a vertical problem and a horizontal problem

The vertical problem is the ball falls 70 meters (I assume) in t seconds

The horizontal problem is he ball proceeds at constant initial speed u for the same t seconds.

Vertical

initial vertical speed = 0

initial height = 70

final height = 0

acceleration = -g = -9.8 m^s^2

0 = 70 + 0 t + (1/2)(9.8) t^2

4.9 t^2 = 70

t = 3.78 seconds in the air

Now you did not say what initial speed u was, although I am sure the problem in the book did so and also included the missing units. So

distance = rate * time = u * 3.78 meters

- physics -
**Henry**, Friday, February 4, 2011 at 6:00pm
Anonymous, check your 2-2-11,12:26am post.

- physics -
**Anonymous**, Friday, February 4, 2011 at 8:08pm
I need to know the initial velocity and the units are meters

## Answer this Question

## Related Questions

- Physics - a) A cannonball is fired horizontally from the top of a cliff. The ...
- physics - a cannonball is fired horizontally from the top of a cliff. the cannon...
- Physics - Someone posted the question below, stating that they knew the answer ...
- physics - A cannon is mounted on a tower above a wide, level field. The barrel ...
- physics - 10. A cannon elevated at an angle of 35º to the horizontal fires a ...
- physic - A cannon ball is fired at an angle of 30° above horizontal with an ...
- physics - King Arthur's knights fire a cannon from the top of the castle wall. ...
- physics - King Arthur's knights fire a cannon from the top of the castle wall. ...
- physics - a projectile is fired at an angle of 27 above the horizontal from the ...
- physics. - A 20.0 kg cannon ball is fired from a cannnon with muzzle speed of ...

More Related Questions