Besides its weight, a 2.8 kg object is subjected to one other constant force. The object starts from rest and in 1.20s experiences a displacement of (4.20i - 3.30j) m, where the direction of j is the upward vertical direction. Determine the other force.
I don't understand exactly what their asking for....is it an exact number or the direction? How do would you solve this? Help, thanks.
2006-10-23 14:23:28 · 5 answers · asked by andrew c 1 in Science & Mathematics ➔ Physics
Well force is a vector quantity so it has a magnitude (number)) and a direction.
The simple way to break the problem down, and they've given you the data that way is vertical and horizontal.
The time is 1.2 seconds
Change in the vertical direction is - 3.3 meters with postive being up.
F = ma so acceleration = F/m
Vertical distance = -3.3 Meters = ((g/2 +Vertical Force/2m)(time^2)
g = 9.8 m/s^2
m = 2.8 Kg
time = 1.2 sec
Solve for vertical component of the force
Since the horizontal translation has nothing to do with gravity.
The horizontal distance = 4.20 Meters = (Horizontal Force/ 2m)(time^2)
Solve for Horizontal Force
Answer = Horizontal Force(i) + Vertical Force (j)
Have fun.
2006-10-23 14:38:13 · answer #1 · answered by Roadkill 6 · 0⤊ 0⤋
You have two forces acting on the weight. One is known. the force of gravity which is m*g in the vertical (j) (downward) direction. The other force F is unknown, both in magnitude and direction. This force has two components, Fi and Fj (horiz and vert). The vertical acceleration of the weight is aj = (Fj/m)-g (taking upward as the positive direction), the horizontal acceleration is ai = Fi/m. The vertical displacement is given by .5*aj*t^2 = .5*(Fj/m-g)*t^2, the horizontal displacement is .5*ai^t^2 = .5*(Fi/m)*t^2. This gives the two equations:
.5*(Fj/m-g)*t^2 = -3.3
.5*(Fi/m)*t^2 = 4.2
m, g, and t are known.
From these, solve for Fj and Fi; the force vector is then (Fj)*j + (Fi)*i. Its magnitude is √(fj^2+Fi^2, and angle is arctan(Fj/Fi)
2006-10-23 21:58:18 · answer #2 · answered by gp4rts 7 · 0⤊ 0⤋
Weight is a drive prompted by means of gravity. The weight of an item is the gravitational drive among the item and the Earth. The extra mass the item has the higher its weight shall be. Weight is a drive, so it is measured in newtons. On the outside of the Earth an item with a mass of one million kg has a weight of approximately 10 N.
2016-09-01 01:42:10 · answer #3 · answered by ? 4 · 0⤊ 0⤋
Go and ask the professor of the course! That might help you lots.
2006-10-23 14:25:10 · answer #4 · answered by shaydn e 2 · 0⤊ 3⤋
try looking up answers on howthingswork.com
2006-10-23 14:24:47 · answer #5 · answered by Mustang gt 500 2 · 0⤊ 3⤋