Physical science quiz three momentum • Name:

1. ____________________ Potential energy is equal to mass m × acceleration of gravity g × height h. (PE = mgh) Calculate the potential energy of a 5 gram marble 60 cm high on banana leaf ramp. Use 980 cm/s² for g.
2. ____________________ Consider energy to be conserved. Kinetic energy is: $\text{KE}=\frac{1}{2}m{v}^2$ where m is the mass and v is the velocity. Calculate the predicted velocity of the marble at the bottom of the banana leaf ramp.
3. ____________________ If one marble collides with a line of five marbles on a ruler track, how many marbles are ejected and roll on off the track?
4. ____________________ If three marbles collide with a line of five marbles on a ruler track, how many marbles are ejected and roll on off the track?
5. Why do you think the marbles know what to do?
6. ____________________ A 20.2 g taw covers 30.0 cm in 0.59 seconds. What is the speed of the taw?
7. ____________________ A 20.2 g taw covered 30.0 cm in 0.59 seconds. What is the linear momentum of the taw? Note: Momentum is mass × velocity
8. ____________________ A 20.2 g taw covered 30.0 cm in 0.59 seconds. What is the kinetic energy of the taw? Note: $\text{KE}=\frac{1}{2}m{v}^2$
9. ____________________ Why do you think the water stayed in the glass on Wednesday?
10. ____________________ Why do you think the balloons did not become equal in size on Wednesday?

For more information on the cgs unit of energy, the erg, see An Erg is an Ant Pushup

Physci spring 2008 • Physci • Courses • COMFSM