Question

Learning Goal: To understand the relationship between force, impulse, and momentum. The effect of a net force ΣF⃗ acting on an object is related both to the force and to the total time the force acts on the object. The physical quantity impulse J⃗ is a measure of both these effects. For a constant net force, the impulse is given by J⃗ =F⃗ Δt. The impulse is a vector pointing in the same direction as the force vector. The units of J⃗ are N⋅s or kg⋅m/s. Recall that when a net force acts on an object, the object will accelerate, causing a change in its velocity. Hence the object's momentum (p⃗ =mv⃗ ) will also change. The impulse-momentum theorem describes the effect that an impulse has on an object's motion: Δp⃗ =J⃗ =F⃗ Δt. So the change in momentum of an object equals the net impulse, that is, the net force multiplied by the time over which the force acts. A given change in momentum can result from a large force over a short time or a smaller force over a longer time.

Impulse on a Baseball 12 of 15 > Constants The impulse of an object is also related to its change in momentum. Once the impulse is known, it can be used to find the change in momentum, or if either the initial or final momentum is known, the other momentum can be found. Keep in mind that j = Ap= m( - ). Because both impulse and momentum are vectors, it is essential to account for the direction of each vector, even in a one-dimensional problem. - Part D Learning Goal: To understand the relationship between force, impulse, and momentum The effect of a net force EF acting on an object is related both to the force and to the total time the force acts on the object. The physical quantity impulse I is a measure of both these effects. For a constant net force, the impulse is given by j = Fat The impulse is a vector pointing in the same direction as the force vector. The units of J are Nsor kg .mn/n, Recall that when a net force acts on an object, the object will accelerate, causing a change in its velocity. Hence the object's momentum (= m) will also change. The impulse-momentum theorem describes the effect that an impulse has on an object's motion: Assume that a pitcher throws a baseball so that it travels in a straight line parallel to the ground. The batter then hits the ball so it goes directly back to the pitcher along the same straight line. Define the direction the pitcher originally throws the ball as the +x direction. The impulse on the ball caused by the bat will be in the negative x direction. Submit Previous Answers Correct Part E Figure 1 of 2 Now assume that the pitcher in Part D throws a 0.145-kg baseball parallel to the ground with a speed of 32 m/s in the +x direction. The batter then hits the ball so it goes directly back to the pitcher along the same straight line. What is the ball's x-component of velocity just after leaving the bat if the bat applies an Impulse of -8.4 N .s to the baseball? Enter your answer numerically in meters per second using two significant figures. F(N) Templates Symbols uodo redo reset keyboard shortcuts help U = m/s 12.000 Submit Request Answer 0.0007 Provide Feedback Next >

Please answer part e

Answer 1

J= Impulse

V_f=Final velocity

V_i=Initial velocity

m=Mass of the object

J=m(V_f-V_i/) =

V_f= J/m + V_i= (-8.4/0.145) + 32

V_f= -25.93 m/s

Final velocity of the ball is 25.93m/s in -x direction