Which one of the following statements about the Wright brothers is not true?

A. They felt they had to get into the air themselves to further test their wing-warping technique.

B. On December 17, 1903, the Flyer flew for two minutes and 1200 feet.

C. They wanted to first develop an aircraft that would fly and could be controlled in flight, and then add a power plant.

D. On their first attempt to fly, Wilbur was at the controls. The Flyer became airborne but stalled and fell back into the sand. It was slightly damaged.

Tom is having a problem with his washing machine. he notices that the machine vibrates violently at a frequency of 1500 rpm due to an unknown rotating unbalance. the machine is mounted on 4 springs each having a stiffness of 10 kn/m. tom wishes to add an undamped vibration absorber attached by a spring under the machine the machine working frequency ranges between 800 rpm to 2000 rpm and its total mass while loaded is assumed to be 80 kg a) what should be the mass of the absorber added to the machine so that the natural frequency falls outside the working range? b) after a first trial of an absorber using a mass of 35 kg, the amplitude of the oscillation was found to be 10 cm. what is the value of the rotating unbalance? c) using me-3.5 kg. m, find the optimal absorber (by minimizing its mass). what would be the amplitude of the oscillation of the absorber?