Momentum worksheet

1. Velocity: 16.25 m/s

1. Momentum is mass times velocity, so divide the momentum by the mass to get the velocity

   $\frac{\mathrm{32,500}}{\mathrm{2,000}}$$=16.25\text{\hspace{0.17em}m/s}$

2. Mass: 1,666,666.67 g

1. Momentum is mass times velocity, so divide the momentum by the velocity to get the mass

   $\frac{\mathrm{25,000}}{15}$$=\mathrm{1,666.666667}\text{\hspace{0.17em}kg}$

2. Change the answer to g, the unit you picked: divide by 0.001

   $\frac{\mathrm{1,666.666667}}{0.001}$$=\mathrm{1,666,666.666667}\text{\hspace{0.17em}g}$

3. Mass: 1,444.44 kg

1. Momentum is mass times velocity, so divide the momentum by the velocity to get the mass

   $\frac{\mathrm{26,000}}{18}$$=\mathrm{1,444.444444}\text{\hspace{0.17em}kg}$

4. Impulse (change in momentum): 259.52 lb·ft/s

1. Change contact time to s, the standard unit the formula uses (1 ms = 0.001 s)

   $46\text{\hspace{0.17em}ms}\times 0.001$$=0.046\text{\hspace{0.17em}s}$

2. Multiply the average force by the contact time. That gives the impulse, which is the change in momentum

   $780\times 0.046$$=35.88\text{\hspace{0.17em}N·s}$

3. Change the answer to lb·ft/s, the unit you picked: divide by 0.138254954376

   $\frac{35.88}{0.138254954376}$$=259.520537\text{\hspace{0.17em}lb·ft/s}$

5. Momentum: 29,000 kg·m/s

1. Multiply the mass by the velocity to get the momentum (p = m × v)

   $\mathrm{1,450}\times 20$$=\mathrm{29,000}\text{\hspace{0.17em}kg·m/s}$

6. Contact time: 0.05 s

1. Impulse is force times time, so divide the impulse by the average force to get the contact time

   $\frac{36}{800}$$=0.045\text{\hspace{0.17em}s}$

7. Momentum: 39,600 kg·m/s

1. Multiply the mass by the velocity to get the momentum (p = m × v)

   $\mathrm{1,800}\times 22$$=\mathrm{39,600}\text{\hspace{0.17em}kg·m/s}$

8. Impulse (change in momentum): 4.78 lbf·s

1. Change contact time to s, the standard unit the formula uses (1 ms = 0.001 s)

   $50\text{\hspace{0.17em}ms}\times 0.001$$=0.05\text{\hspace{0.17em}s}$

2. Multiply the average force by the contact time. That gives the impulse, which is the change in momentum

   $425\times 0.05$$=21.25\text{\hspace{0.17em}N·s}$

3. Change the answer to lbf·s, the unit you picked: divide by 4.448221615261

   $\frac{21.25}{4.448221615261}$$=4.77719\text{\hspace{0.17em}lbf·s}$

9. Momentum: 5,665.19 lbf·s

1. Multiply the mass by the velocity to get the momentum (p = m × v)

   $\mathrm{1,400}\times 18$$=\mathrm{25,200}\text{\hspace{0.17em}kg·m/s}$

2. Change the answer to lbf·s, the unit you picked: divide by 4.448221615261

   $\frac{\mathrm{25,200}}{4.448221615261}$$=\mathrm{5,665.185366}\text{\hspace{0.17em}lbf·s}$

10. Velocity: 120 km/h

1. Momentum is mass times velocity, so divide the momentum by the mass to get the velocity

   $\frac{\mathrm{30,000}}{900}$$=33.333333\text{\hspace{0.17em}m/s}$

2. Change the answer to km/h, the unit you picked: divide by 0.277777777778

   $\frac{33.333333}{0.277777777778}$$=120\text{\hspace{0.17em}km/h}$