Apendulum that moves through its equilibrium position once every 1.000 s is sometimes called a “seconds pendulum.” what is the period of any seconds pendulum? 1. 4.000 s 2. 2.000 s 3. none of these 4. 1.000 s 5. 0.500 s 6. 0.250 s

The equilibrium position for a pendulum is straight down. If it moves through that position every second then its period is actually 2 seconds. This is because the period is how long it takes to go from one extreme and back again. It will pass through the equilibrium point twice when doing this. Once on the way down and again on the way back.

Distance covered, s = 8ft - 4ft = 4 ftinitial velocity, u = 34 ft/sthe acrobat is moving upwards and therefore, a = -g = -9.81 m/s^2 = 32.19 ft/s^2applying equation of motion; s = ut -1/2gt^2then,4 = 34t -1/2*32.19t^24 = 34t - 16.095t^2rearranging; -16.095t^2 + 34t - 4 = 0solving the quadratic equation; t = {-34 +/- sqrt [34^2 - 4(-16.)]}/2(-16.095) = 1.06 +/- 0.93 = 0.13 or 1.99the acrobat will take 0.13 seconds to be at 8 ft above the ground. additionally, once at the maximum height, the acrobat will move down and be at the same spot (that is height) after 1.99 seconds moving down.