Physics - September 2007

when the pilot releases a radar decoy. The horizontal distance between the release point and the point where the decoy strikes the ground is 700 m. (Neglect air resistance.)
a) How high was the plane when the decoy was released?
m
(b) How long was the decoy in the air?
s

Hints:
the answer are:
898.3m for a
10.04s for b
please just show the working

2007-09-12 13:02:20 · 1 answers · asked by Wonder 2

The punter on a football team tries to kick a football so that it stays in the air for a long "hang time." If the ball is kicked with an initial velocity of 23.6 m/s at an angle of 58.5° above the ground, what is the "hang time"?

___s

2007-09-12 12:35:46 · 3 answers · asked by Marianna E 1

the HARP (High Altitude Research Project) gun can fire an 84.00 kg projectile containing scientific instrument staright up to an altitude of 179 km. If we pretend there is no air resistance , what muzzle spees is required to attain this altitude (m/s)? How long does the projectile remain at a height in excess of 100 km, the height of interest for high-altitude research (s)?

2007-09-12 12:35:11 · 1 answers · asked by Anonymous

if it is to be airboure after a takeoff run of 240 m? B) How long does it take the aircraft to become airborne?

2007-09-12 12:30:01 · 1 answers · asked by mary s 1

a boat is traveling at 77m/min and travels for a total of 10sec. how much distance did the boat cover.

2007-09-12 12:26:52 · 4 answers · asked by *Natasha* 1

A football player kicks a football with an initial speed of 13 m/s at an angle above the horizontal of 30 degrees.

a.) what are the initial components of the balls velocity?
b.) How much time will it take to reach the peak of it's motion?
c.) How much time (from the instant of the kick) will it take to reach the final position?
d.) What is the max height the ball will reach?
e.) How far from the football player (in the horizontal direction) will the ball reach it's peak?
f.) What is the final x position of the ball when it strikes the ground (assuming that x (knot) = 0)

Would really appreciate any help, even if it is just describing the steps/formulas and leaving me to do the calculations. Thanks!

2007-09-12 12:25:39 · 2 answers · asked by Jamie H 1

the question is: If the resistance of a circuit remains constant while the voltage across the circuit decreases to half its former value, what change occurs in the current?

I'm thinking that the current decreases to half of what it would be otherwise. I'm I correct or not? Thanks mucho!

2007-09-12 12:20:20 · 1 answers · asked by platypus 2

I need help with the following problem, and it would help if you could break down the steps for me so I can follow along. I also need to know if the car is decelerating or accelerating as well. Any help is appreciated, thanks!

A car is traveling to the left, which is the negative direction. The direction of travel remains the same throughout this problem. The car's initial speed is 27.0 m/s, and during a 5.1 s interval, it changes to the following final speeds. In each case, find the acceleration (magnitude and algebraic sign) and whether or not the car is decelerating.
(a) The final speed is 28.1 m/s.
m/s2 and the car is ---Select--- accelerating decelerating
(b) The final speed is 21.5 m/s.
m/s2 and the car is ---Select--- accelerating decelerating

2007-09-12 12:08:43 · 1 answers · asked by yummy_girlscout 1

at what speed in m/s is the ball thrown

2007-09-12 12:02:36 · 1 answers · asked by Anonymous

Lets say the tunnel is pressurized, oxegen available. and you jump in, are you goin to come out of the other side, elevate in the middle,perhaps get to the middle and keep falling up and down as gravity weakins you go up then reach a point where it gets stronger then you'l go down?

2007-09-12 11:57:25 · 3 answers · asked by ROCO 2

What are electrons made up of? because today my chemistry teacher told us they were made of of quarks. and i was pretty sure that only protons and neutrons were made up of quarks. and that electrons are leptons, which are fermions, which arent made up of quarks at all. im right arent i?

2007-09-12 11:51:11 · 1 answers · asked by Anonymous

Dear Yahoo Answers,
Please Help with this confusing question..Which of the following situations does NOT involve any work being done?


(a) A 10 kg crate is lifted 2 metres
(b) A car is pushed along a road
(c) A spacecraft travels through the solar system without being affected by air resistance or gravity
(d) A skateboard rolls to a stop
(e) A book sits on a desk

Any contribution will be appreciated.

2007-09-12 11:25:24 · 5 answers · asked by Menor S 1

2007-09-12 11:21:35 · 43 answers · asked by RICH71 1

I belive we have reached the technological level to actually build a force field, it has to be possible, perhaps using focused electrical current?if electricity cant do it what possibly can? any studies on it?

2007-09-12 10:15:24 · 4 answers · asked by ROCO 2

I wonder if there's a way to scientifically separate sound heard from a speaker and sound heard live?

2007-09-12 10:08:39 · 1 answers · asked by Billy188 1

An astronaut on a distant planet wants to determine its acceleration due to gravity. The astronaut throws a rock straight up with a velocity of 16.2 m/s and measures a time of 22.0 s before the rock returns to his hand. What is the acceleration due to gravity on this planet?

I have no clue how to answer this. I tried the equation V=Vo + at, but the answer i get (.736 m/s^2) is not right. How do I do this?

2007-09-12 09:56:11 · 7 answers · asked by jULIAN C 2

10:00. When will Lee meet Mark?

2007-09-12 08:56:24 · 5 answers · asked by V for Vindicated 1

And how did someone split it?

2007-09-12 08:27:08 · 5 answers · asked by Chloelouise 2

A record of travel along a straight path is as follows.
1. Start from rest with constant acceleration of 2.71 m/s^2 for 15.1 s.
2. Constant velocity for the next 3.47 min.
3. Constant negative acceleration -9.68 m/s^2 for 3.39 s.

a) What was the average speed for leg 3 of the trip in m/s?
b) What was the average speed for the complete trip in m/s??

I tried this problem and I keep getting it wrong, I have no idea what I am doing wrong! Please help! THANKS!

2007-09-12 08:19:11 · 4 answers · asked by lola 1

Using dimensional analysis, find an expression for v in terms of p and d. Thanks for your help. I was stomped on this one.

2007-09-12 08:13:15 · 2 answers · asked by Anonymous

You roll a ball horizontally off the edge of a table. The instant the ball leaves the table its 1.00 m off the floor, and is moving horizontally. It hits the floor after traveling .750m to the right What was its speed as it left the table?

2007-09-12 08:12:38 · 1 answers · asked by BobLong 1

This is due tonight and I DO NOT understand. How do you due this problem, and what is the answer?

"A freely falling object requires 1.90 seconds to fall the last 38.0 m before it reaches the ground. From what height did the object fall?"

This is not in my book. None of the formulas work because you have to know more variables than I am given. PLEASE help me.

2007-09-12 08:10:37 · 4 answers · asked by justme 4

2007-09-12 08:10:16 · 1 answers · asked by BobLong 1

A child throws a rock upwards with a speed of 40.0 m/s. At the end of 10 seconds, (a) where is the stone and (b) at what speed is the stone moving?

My answers came out to:

(a) 890 m
(b) 138 m/s

The math seems right to me, but I feel icky about the high distance... Thanks.

2007-09-12 07:49:15 · 4 answers · asked by labelapark 6

2007-09-12 07:45:05 · 2 answers · asked by Alexander 6

2007-09-12 07:43:19 · 3 answers · asked by Brainybutcute 1

emerging from the gun with a speed of 250 m/s.
a.At what horizontal distance from the firing point does it strike the ground?
m
b.What is the magnitude of the vertical component of its velocity as it strikes the ground?
m/s
Answer:
1107m for a
43.4m/s for b
just show the work

2007-09-12 07:42:45 · 5 answers · asked by Wonder 2

2007-09-12 07:34:58 · 2 answers · asked by Anonymous

I would like to know the distance between the tip and trough of the same antinode on an electric guitar string.
My estimate is around 0.001m, but i'm really not sure!

2007-09-12 07:33:45 · 1 answers · asked by PTP 4

2007-09-12 07:29:05 · 2 answers · asked by Anonymous