Friday

September 19, 2014

September 19, 2014

Posted by **suzanne** on Thursday, February 28, 2013 at 1:45am.

- physics -
**drwls**, Thursday, February 28, 2013 at 2:32amNeglecting air friction, the time it will take the rock to hit the water is

sqrt(2H/g) = 2.857 seconds. That means the sound of the splash takes 3 - 2.857 = 0.143 seconds to be heard, after hitting water. Sound travelled 49.05 m in that time. Since the cliff is 40 m high, the horizontal distance travelled by the rock was (from the Pythagorean theorem)

sqrt[(49.05)^2 -(40)^2] = 28.4 m

The rock's initial speed (and constant horizontal speed) was 28.4 m/2.857 s = 9.84 m/s

**Answer this Question**

**Related Questions**

physics - A soccer player kicks a rock horizontally off a 40.0 m high cliff into...

physics - A soccer player kicks a rock horizontally off a 41.7 m high cliff into...

physics - A soccer player kicks a rock horizontally off a cliff 42.9 m high into...

physic - Question Part Points Submissions Used A soccer player kicks a rock ...

Physics - A soccer player kicks a rock horizontally off the a 40 m high cliff ...

physics - Soccer player #1 is 7.31 m from the goal, as the figure shows. If she ...

physics - Soccer player #1 is 7.31 m from the goal, as the figure shows. If she ...

physics - Soccer player #1 is 8.6 m from the goal. If she kicks the ball ...

physics - To estimate how high the cliff is you throw a rock off the edge and 7....

Physics - A rock is dropped from a sea cliff 400m high.If the speed of sound is ...