# Physics

A rock is dropped from a height of 100m.

a) how long does it take to fall the first 50m?

b)How long does it take to fall the last 50m?

Which equation would I use to solve this problems with?

For a) use s=(1/)g*t^2 where s=50m and g=9.8m/s^2 and solve for t.
For b)use s=(1/)g*t^2 where s=1000m and g=9.8m/s^2, solve for t and subtract the result of part a).
You use the same formula, but you look at the total time minus some partial time. Does that make sense?

1. 👍
2. 👎
3. 👁
1. A stone propelled from a catapult with a speed of 50m-s attains a height of 100m calcutate

1. 👍
2. 👎

## Similar Questions

1. ### physics

A boy throws a rock with an initial velocity of 2.47 m/s at 30.0 degrees above the horizontal. How long does it take for the rock to reach the maximum height of its trajectory?

2. ### Physics

A rock is dropped from the top of a tall tower. Half a second later another rock, twice as massive as the first, is dropped. Ignoring air resistance, (A) the distance between the rocks increases while both are falling. (B) the

3. ### physics

An object is dropped from a height of 12m.At what height is the rock kinetic energy and its potential energy be equal?

4. ### Physics

A bomb dropped from a balloon reaches the ground in 30seconds .determine the height of the balloon if it is at rest in the air and if it is ascending with a speed of 100m/sec when the balloon is dropped

1. ### Physics

A rock is dropped from a height of 2.7 m. How fast is it going when it hits the ground?

2. ### Math

If the flight of a rocket can be modelled by the function h=-4.9t^2+49t+2.5. Where h is height in meters and t is time in seconds. How long was the rocket above 100m? I know that you have to find the two times when the rocket hits

3. ### Math

If a rock falls from a height of 50 meters on​ Earth, the height H​ (in meters) after x seconds is approximately H(x)=50-4.9x^2 1. ​What is the height of the rock when x=1.6 ​seconds? 2. ​When is the height of the rock 5

4. ### Physics

A rock is dropped of the side of a bridge and hits the water below 4s later. a. What was the rock’s velocity when it hit the water? b. What was the rock’s average velocity as it fell? c. What is the height of the bridge above

1. ### Math

Suppose an object is dropped from a height h0 above the ground. Then its height after t seconds is given by h = −16t 2 + h0, where h is measured in feet. Use this information to solve the problem. A ball is dropped from the top

2. ### Physics

A bomb dropped from a balloon reaches the ground in 30secs . determine the height of the balloon.(a) if it is at the rest in the air.(b) if it is ascending with a speed of 100m/s when the bomb is dropped

3. ### physics

a rock is thrown straight up and reaches a height at 10 meters. 1.how long was the rock in the air 2.what is the initial vvelocity of the rock?

4. ### physic

Martha drops a 1 kg rock off the top of Black Oak Canyon which is 100m deep. What is the KE of the rock the instant before it hits bottom? Hint: Conservation of energy states that PE = KE