Answer:
The net force acting on the chair is 8 newtons, and the chair moves toward the left.
Explanation:
We can better understand this problem if we analyze it through a free body diagram. This free body diagram is attached as an image.
If we make a sum of forces acting over the chair we can find -20 + 12 = -8 [N]
The minus sign indicates that the chair is moving to the left.
Answer:
(a)
(b)
1120 N
Explanation:
Change in velocity, is given by subtracting the initial velocity from the final velocity and expressed as
Where v represent the velocity and subscripts f and i represent final and initial respectively. Since the ball finally comes to rest, its final velocity is zero. Substituting 0 for final velocity and the given figure of 8 m/s for initial velocity then the change in velocity is given by
To find then we substitute 7 kg for m and -8 m/s for
therefore
(b)
The impact force, F is given as the product of mass and acceleration. Here, acceleration is given by dividing the change in velocity by time ie
Substituting t with 0.05 s then
Since F=ma then substituting m with 7 Kg we get that F=7*-160=-1120 N
Therefore, the impact force is equivalent to 1120 N
