Tuesday
September 30, 2014

Homework Help: physics

Posted by tibby on Monday, October 10, 2011 at 11:24pm.

A cannon with a muzzle speed of 1008 m/s is used to start an avalanche on a mountain slope. The target is 1900 m from the cannon horizontally and 802 m above the cannon. At what angle, above the horizontal, should the cannon be fired? (Ignore air resistance.)

Someone help please. I've tried two different approaches to this problem which were done by other students also and it worked for the same question but with different numbers. I've used this formula

x= horizontal distance of cannon from target y= meters above the cannon
g= 9.8 u= cannon's muzzle speed
r= unknown a= angle at which cannon should be fired
b= theta
--------------------------------
r = sqrt(x^2+y^2)
cos(b)= x/r
r*sin(2a-b)=(9.8*2^2)+y

i got 62.429 degree

and the second method used was this formula

h=(v^2sin^2theta)/2(9.8)

and i've gotten 11.643 degree

both of them are wrong, please help :(

Due tonight at 12am

Answer this Question

First Name:
School Subject:
Answer:

Related Questions

physic--help --- - one of the main battery of cannons protecting the entrance to...
Physics - A cannon is mounted on a truck that moves forward at a speed of 5 m/s...
physics - A spring cannon is fastened to a glider at rest on a horizontal ...
physics - Suppose a fixed cannon is to fire a projectile at an enemy tank, which...
physics - A railway flat car is rushing along a level frictionless track at a ...
Physics - A cannon is mounted on a truck that moves forward at a speed of 5 m/s...
physics - Suppose a fixed cannon is to fire a projectile at an enemy tank, which...
Physics - A revolutionary cannon, with a mass of 2000kg, fires a 20kg ball ...
vector geometry - Suppose a fixed cannon is to fire a projectile at an enemy ...
Physics - A 500 kg cannon rests on wheels that are free to roll. The cannon ...

Search
Members