a boy stands 80m in front of a tall cliff and produces sound by clapping two planks together. A girl standing next to him time the return of the echo at 0.5. how fast does sound wave travel in this place

N Rutherford's gold foil experiment the alpha particles pass through which part of the atom? A. the nucleus B. the proton shield C. the electron cloud D. the valence electron shell

Where do stars from?

Why does water have a high surface tension? Hydrogen bonding keeps water molecules close together. Water is a liquid at room temperature. Water molecules contain 18 electrons. The lengths of the bonds in water molecules can change.

A shot-putter accelerates a 7.2 kg shot from rest to 17 m/s. what work did the shot-putter do on the ball?

The Southwest Indian Ridge, shown in red, moves at an average rate of 20 mm/year, making it among the ultraslow spreading ridges" on Earth. In how many years will the ridge move 100 mm?

What material are oil pipelines made from?

3/129 A 175-lb pole vaulter carrying a uniform 16-ft, 10-lb pole approaches the jump with a velocity v and manages to barely clear the bar set at a height of 18 ft. As he clears the bar, his velocity and that of the pole are essentially zero.

A few years ago, Serena Williams dived to hit a tennis ball right after it bounced off the ground. The ball bounced on the ground 10.3 m from the net, and after Serena hit the ball it flew over the 0.

A force of 1.25x103N is required to lift an object that is under the influence of an acceleration due to gravity of 7.86ft/sec2. What is the object's mass in kilograms?

Which of these events is an example of the Doppler shift? The amplitude of a wave on a string increases as the frequency decreases. The amplitude of sound from a tuning fork decreases due to damping.