1. A small bullet is fired into a large piece of wood. After the bullet penetrates the wood, the assembly moves as one unit along a low-friction track in the direction of travel of the bullet. After the bullet is stuck in the piece of wood, is the momentum of the wood (not including the bullet; assuming the piece of wood was initially at rest) greater than, equal to, or less than the initial momentum of the bullet? a. The momentum of the wood is greater than the initial momentum of the bullet
b. The momentum of the wood is greater than the initial momentum of the bullet.
c. The momentum of the wood is less than the initial momentum of the bullet

2. Is the combined kinetic energy of the bullet and the wood after the bullet is stuck in the wood greater than, equal to, or less than the initial kinetic energy of the bullet?

a. The combined energy is less than the initial kinetic energy of the bullet.
b. The combined energy is equal to the initial kinetic energy of the bullet.
c. The combined energy is greater than the initial kinetic energy of the bullet.

If you want to change the pitch of a sound, you have to change the

Search coils and credit cards. one practical way to measure magnetic field strength uses a small, closely wound coil called a search coil. the coil is initially held with its plane perpendicular to a magnetic field. the coil is then either quickly rotated a quarter-turn about a diameter or quickly pulled out of the field. (a) derive the equation relating the total charge q that flows through a search coil to the magnetic-field magnitude b. the search coil has n turns, each with area a, and the flux through the coil is decreased from its initial maximum value to zero in a time ∆t. the resistance of the coil is r, and the total charge is q = i∆t, where i is the average current induced by the change in flux. (b) in a credit card reader, the magnetic strip on the back of a credit card is rapidly “swiped” past a coil within the reader. explain, using the same ideas that underlie the operation of a search coil, how the reader can decode the information stored in the pattern of magnetization on the strip. (c) is it necessary that the credit card be “swiped” through the reader at exactly the right speed? why or why not?

Atruck driver is attempting to deliver some furniture. first, he travels 8 km east, and then he turns around and travels 3 km west. finally, he turns again and travels 13 km to his destination. what is the drivers distance