I'm really stumped on 3 of my physics questions.. Ive been able to find a few things but theres so many equations and variables I've gotten myself lost.. if anyone could help it would be greatly appreciated! A 25.0 g bullet strikes a 0.600 kg block attached to a fixed horizontal spring whose spring constant is 6700 N/m and set it into vibration with an amplitude of 21.5 cm. What was the speed of the bullet before impact if the two objects move together after the impact? -not sure what I need to do in this case? tried finding the total energy when v=0 and x= +- A, but that lead me no where The other question... The length of a simple pendulum is 0.66 m, the pendulum bob has a mass of 310 grams, and it is released at an angle of 12º to the vertical. (a) With what frequency does it vibrate? Assume SHM. (b) What is the pendulum bob’s speed when it passes through the lowest point of the swing? (c) What is the total energy stored in this oscillation, assuming no losses? Found F= 0.9Hz not sure how to incorporate the angle into the equation to solve the rest? Finally... If two successive overtones of a vibrating string are 280 Hz and 350 Hz, what is the frequency of the fundamental? THANKS to anyone who can help me out!