# Physics

posted by .

Someone posted the question below, stating that they knew the answer to part A but needed help with part B. Well even with the answer for A, I can't figure it out! Can you take a step back from the question below to show me the steps for solving part A? I've been working on this for 2 days!

thanks!

This question was submitted by Sam on Friday, September 26, 2008 at 8:59pm. The subject of this question is Physics.

--------------------------------------------------------------------------------

a) A cannonball is fired horizontally from the top of a cliff. The cannon is at height H = 100 m above ground level, and the ball is fired with initial horizontal speed v_0. Assume acceleration due to gravity to be g = 9.80 m/s^2. Assume that the cannon is fired at time t = 0 and that the cannonball hits the ground at time tg. What is the y position of the cannonball at the time tg/2?

I got 75m and I know that one is right.

I need help with part b
Given that the projectile lands at a distance = 110 from the cliff, as shown in the figure, find the initial speed of the projectile, .

• Physics -

If you know tg, you know the time it was in the air.

Horizontal distance=initialhorizontal veloicty*tg

solve for initialhorizonalveloicty vo

## Similar Questions

1. ### physics

I am a bit of an overachiever, and I've developed a habit of reviewing subjects during the summer before I take them in the new year. I was just looking through the posts on this site for review, when a certain physics question caught …
2. ### Physics

The intensity of sunlight reaching the earth is 1360 W/m^2 Part A: Assuming all the sunlight is absorbed, what is the radiation-pressure force on the earth?
3. ### Technology

I posted this question a while back on jiskha. i don't even remember if i got an answer or not. here it is: the montior is a part of the computer that would be considered a(n) a. input device b. processing device c. output device d. …
4. ### Technology

'I posted this question a while back on jiskha. i don't even remember if i got an answer or not. here it is: the montior is a part of the computer that would be considered a(n) a. input device b. processing device c. output device …
5. ### Chemistry

I was given a question on an assignment and I can't figure it out. The question is A student collects 90ml of oxygen gas over water at 25c and a total pressure of 99.3kPa from the decomposition of KClO3. 2KClO3(s)-> 2KCl(s)+ 3O2 …
6. ### Math

Yesterday someone posted my exact question, but I can't find the answer. What is area/perimeter of capital letters: I, U, and J?
7. ### Physics

Can anyone answer part 3 for me? I've tried so many incorrect answers that I've already given up: 1.00, 1.50, 2.00, 3.00, 9.40 Question: A slingshot obeying Hooke's law is used to launch pebbles vertically into the air. You observe
8. ### Physics

In an attempt to reduce the extraordinarily long travel times for voyaging to distant stars, some people have suggested traveling at close to the speed of light. Suppose you wish to visit a star which is 410 ly away, and that you want …
9. ### Chemistry

Part 1: Each molecule of NO2, nitrogen dioxide, consists of 1 atom of N and 2 atoms of O. If you have 0.155 g. of NO2, how many molecules of NO2 do you have ?
10. ### AP Physics B

I have one our part question left that I just don't understand! Please help me!! Part 1 An 11.6 kg block of metal is suspended from a scale and immersed in water as in the ﬁgure. The dimensions of the block are 12.9 cm × 9.7 …

More Similar Questions