An unknown tuning fork is sounded along with a tuning fork whose ...

[lbcchick]

An unknown tuning fork is sounded along with a tuning fork whose frequency is 256. Hz and a beat frequency of 3. Hz is heard. What is the frequency of the unknown tuning fork?
 
  A) It must be 256 Hz.
  B) It must be 259 Hz.
  C) It could be either 253 Hz or 259 Hz; there is no way to tell.
  D) It must be 253 Hz.

Question 2

A 2200. kg auto moving at 12.0 m/s runs into a 3800. kg truck which is moving in the same direction at 5.00 m/s. The collision is perfectly inelastic.
 
  (a) What is the speed of the auto immediately after the collision?
  (b) What percentage kinetic energy did the truck gain in the collision?

[kjo;oj]

Answer to Question 1

C

Answer to Question 2

(a) 7.57 m/s
(b) 129. gain

[lbcchick]

Wow, this really help

[amandalm]

Thanks for the timely response, appreciate it