Frequency = rate of sploosh = 2 per second = 2 Hz.
Period = ( 1/frequency ) = 1/2 second
Speed = (wavelength) x (frequency) = (0.15m) x ( 2/sec) = 0.075 m/s .
Because almost all of the force is done by the weight of the person and the mechanism of the swing itself, when you push someone you only give them an increase in velocity, the acceleration comes from the weight at first and then from gravity when the person is coming down, which is why we bend our legs when coming down
Because the airplane flies at 800 km/h, it will fly 800 km in 1 hour. In order to find how far it travels in 2 hours, we multiply this number by 2. 800*2 = 1600, so the plane will travel 1600 km in 2 hours.