• Oct 12th 2007, 05:58 PM
rcmango
A duck has a mass of 2.6 kg.
As the duck paddles, a force of 0.07 N acts on it in a direction due east.

Also, the current of the water exerts a force of 0.23 N in a direction of 58° south of east. When these forces begin to act, the velocity of the duck is 0.11 m/s in a direction due east.

Find the magnitude and direction (relative to due east) of the displacement that the duck undergoes in 3.2 s while the forces are acting.

the magnitude displayed in meters and the direction in degrees, south of east

• Oct 13th 2007, 03:55 AM
topsquark
Quote:

Originally Posted by rcmango
A duck has a mass of 2.6 kg.
As the duck paddles, a force of 0.07 N acts on it in a direction due east.

Also, the current of the water exerts a force of 0.23 N in a direction of 58° south of east. When these forces begin to act, the velocity of the duck is 0.11 m/s in a direction due east.

Find the magnitude and direction (relative to due east) of the displacement that the duck undergoes in 3.2 s while the forces are acting.

the magnitude displayed in meters and the direction in degrees, south of east

Not too many. Add the forces (vectorally) to get the net force, then divide by the mass to get the acceleration. Then it's just a 2-D motion problem in that direction. (Actually only a 1-D motion problem.... the component of the initial velocity perpendicular to the direction of the acceleration is constant, so there is little work to do with that.)

-Dan
• Oct 13th 2007, 05:43 PM
rcmango
Okay, so if i'm doing this correctly,

i would add the forces of .07 N and .23 N together to get .30 N / 2.6kg

so the acceleration is .11538 ms^2

then now i would use .11538 as the acceleration in the x direction?

if i'm correct so far, whats next?