Thursday

December 18, 2014

December 18, 2014

Posted by **Danielle** on Wednesday, November 6, 2013 at 9:45pm.

If she drops a pebble how fast is it moving after 2 seconds?

How long does it take the pebble to reach the river below?

She has another pebble that she tosses up with initial speed of 8 feet per second. It goes up, then starts falling down to the river below. By the time it reaches the river what is its speed?

- calculus HELP! -
**bobpursley**, Wednesday, November 6, 2013 at 9:53pmCalculus? Hardly.

vf=vi+gt for the firstquestion

second question: h=vi*t-4.9t^2 Vi=0, solve for t

third question

hf=hi+vi*t-4.9t^2

0=100+8t-4.9t^2

solve for time t, then vf=vi-9.8t

but there is an easier method for the last:

vf^2=vi^2+2ad where a=-9.8, d=-100

**Answer this Question**

**Related Questions**

math calculus - A person stands on a bridge that is 100 feet above a river. If ...

algebra - You live near a bridge that goes over a river. The underside of the ...

algebra - You live near a bridge that goes over a river. The underside of the ...

calculus - a suspenion bridge is in a shape of a parabola and has a length of ...

math - an object released from rest will fall 16t^2 feet, t seconds after it is ...

physics - a bungee cord jumper jumps off the new river bridge. the bridge is 876...

calculus - A person drops a stone from a bridge. How high is the bridge if they ...

Physics - A person drops a small rock from a bridge. If it takes 1.70 seconds ...

Math - trigonometry - A bridge is 70m long. From the ends of the bridge the ...

Calculus - An object at rest begins moving horizontally on the x-axis, starting ...