| A T-ball with a mass of 0.6 kg travels in the
air at 10 m/s until it is stopped in the glove of
a shortstop over a period of 0.05 s.
What magnitude of the impulse was im-
parted to the T-ball?
Answer in units of kgm/s.
004 (part 2 of 3) 10.0 points
What is the average net force exerted by
the ball on the glove?
Answer in units of N,

They are similar concepts since they deal with the dynamics of objects having their status of motion changed by the sudden application of a force. The momentum at a given initial time is computed as

[tex]p_o=m.v_o[/tex]

When a force is applied, the speed changes to [tex]v_1[/tex] and the new momentum is

[tex]p_1=m.v_1[/tex]

The change of momentum is

[tex]\Delta p=p_1-p_0=m(v_1-v_o)[/tex]

The impulse is equal to the change of momentum of an object and it's defined as the average net force applied times the time it takes to change the object's motion

[tex]I=F.t=\Delta p[/tex]

Part 1

The T-ball initially travels at 10 m/s and then suddenly it's stopped by the glove. The final speed is zero, so

[tex]\Delta p=0.6\ Kg(0-10\ m/s)=-6\ Kg.m/s[/tex]

The impulse is

[tex]I=\Delta p[/tex]

[tex]I=-6\ Kg.m/s[/tex]

The magnitude is

[tex]|I|=6\ Kg.m/s[/tex]

Part 2

The force can be computed from the formula

[tex]I=F.t[/tex]

The direction of the impulse the T-ball receives is opposite to the direction of the force exerted by the ball on the glove, thus [tex]I_b=6\ kg.m/s[/tex]

[tex]\displaystyle F=\frac{I}{t}=\frac{6\ kg.m/s}{0.05\ s}[/tex]

[tex]\boxed{F=120\ N}[/tex]