Chapter 9, Problem 3STP

To determine

To Choose: The correct option.

Answer to Problem 3STP

Option D. $-3.5\text{kg}\cdot {\text{m}}^{\text{2}}\text{/s}$

Explanation of Solution

Given:

Initial angular momentum, $L_i=7.0\text{kg}\cdot {\text{m}}^{\text{2}}\text{/s}$

Final angular momentum, $L_f=3.5\text{kg}\cdot {\text{m}}^{\text{2}}\text{/s}$

Time taken, $t=5.0\text{s}$

Formula used:

Angular impulse is basically given by the change in the angular momentum,

  $\text{Angular Impulse = }{L}_f-L_i$

Calculation:

Using the given values in above,

  $\begin{array}{c}\text{Angular Impulse = }{L}_f-L_i\\ =\left(3.5-7\right)\text{kg}\cdot {\text{m}}^{\text{2}}\text{/s}\\ \text{= }-3.5\text{kg}\cdot {\text{m}}^{\text{2}}\text{/s}\end{array}$

Conclusion:

Thus, the angular impulse on each wheel is $-3.5\text{kg}\cdot {\text{m}}^{\text{2}}\text{/s}$ .