A simple pendulum is known to have a period, T = 1.55 s. Student A uses their smartphone stopwatch app to measure the total time for 5 oscillations and divides that by 5 to report an average period of T = 1.25 s. Student B uses the same technique but goes old school and whips out his grandpa’s analog stopwatch to come up with an average of T = 1.5 s. What is the most probable source of error that explains the different results?

Ablock of mass m slides on a horizontal frictionless table with an initial speed v0 . it then compresses a spring of force constant k and is brought to rest. the acceleration of gravity is 9.8 m/s2. how much is the spring compressed x from its natural length? 1) x = v0*sqrt(k/(mg)) 2) x=v0*sqrt(m/k) 3) x=v0*((mk)/g) 4) x=v0*sqrt(k/m) 5) x=v0*(m/kg) 6) x=v0*sqrt((mg)/k) 7) x=(v0)^2/(2g) 8) x=v0*(k/(mg)) 9) x=(v0)^2/(2m) 10) x=v0*((mg)/k)