Thursday

January 29, 2015

January 29, 2015

Posted by **Hayli** on Monday, February 20, 2012 at 10:22am.

a. How much time did it take the rock to hit the water?

b. What was its velocity when it was half of the distance to the water?

- Physics -
**drwls**, Monday, February 20, 2012 at 10:54amThe mass of the rock will not affect the answer.

a) Solve 3 = (g/2) t^2 to get t.

b) Solve 1.5 = (g/2) t^2 to get the time to fall half way,

t = sqrt(3/g)

and they use

V = g * t for the velocity V at that time, sqrt(3g). You can also use 3nergy conservation directly to get

the same answer.

**Answer this Question**

**Related Questions**

Physics - A 4.2 kg rock is initially at rest at the top of a cliff. Assuming the...

Physics - You like to swim at a nearby lake. On one side of the lake is a cliff...

Physics - You like to swim at a nearby lake. On one side of the lake is a cliff...

physics - a boy stands on a cliff overlooking a lake below. He throws a rock at ...

Physics - A 3.0 kg rock is initially at rest at the top of a cliff. Assuming the...

physics - A boy sitting on the edge of a vertical cliff fires a rock with a ...

physics - A boy sitting on the edge of a vertical cliff fires a rock with a ...

Physics - A person, standing on a vertical cliff a height h above a lake, wants ...

physics - A child standing on the edge of a sheer cliff wall throws a rock down ...

physics - A 17-kg rock is on the edge of a 103-m cliff. (a) What potential ...