Physics - September 2007

it in the left-hand lane. If brandon accelerates at 5.00 m/s/s

a. how long will it take him to reach a speed of 30.0 m/s

b. how many meters will he travel during this time?

plzz help i'm totally lost

2007-09-10 10:35:47 · 1 answers · asked by Anonymous

A rocket sled has a ,mass of 4440 kg and is propelled by a solid-propellent rocket motor of 890,000-N thrust which burns for 3.9 sec.
a) what is the sled's average acceleration and max speed?
b) This sled has a max acceleration of 30g (30a). How can
that be considering the data given?
c) If the seld travels a distance of 1530m while attaining a top speed of 860 m/sec, what is its average acceleration? How did it attain that high a speed?

2007-09-10 10:32:19 · 2 answers · asked by DJ Ott 1

we had to also make something that we could put aroundt he egg so it would break

2007-09-10 10:23:10 · 5 answers · asked by sarahmichelle876 2

not sure how to do this plzz help v=change in distance/time

2007-09-10 10:15:04 · 4 answers · asked by Anonymous

A uranium projectile fired from a tank in Iraq has a volume of 340.20 cm3 and an intital kinetic energy of
1.98 x 103 kJ. What is the muzzle velocity of the tank's gun (m/s)?
The density of uranium is 18.95 g/cm3.
I am unsure where to begin. I use the formula E(kinetic) = 1/2 m * v^2. Do I set d = m/v to determine the mass and then proceed forth from there?

2007-09-10 10:14:19 · 2 answers · asked by sleepthei 3

A young woman named Kathy Kool buys a sports car that can accelerate at the rate of 5.46 m/s^2. She decides to test the car by drag racing with another speedster, Stan Speedy. both start from rest, but experienced Stan leaves the starting line 1.172 before kathy. Stan moves with a constant acceleration of 3.95 m/s^2 and Kathy maintains an acceleration of 5.46 m/s^2

Find the time it takes Kathy to overtake Stan. Answer in units of s.

Find the distance she travels before she catches up with him. Answer in units of m.

Find the speed of Stan's car at the instant she overtakes him. Answer in units of m/s.

Find Kathy's speed at thtat instant. Answer in units of m/s.

2007-09-10 10:10:41 · 1 answers · asked by Jaweida S 1

A surveillance satellite circles Earth at a height of h miles above the surface. Suppose that d is the distance, IN MILES, on the surface of the Earth that can be seen from the satellite.

(a) Find an equation that relates the central angle theta to the height h.

(b) Find an equation that relates the observable distance d and theta.

(c) Find an equation that relates d and h.


NOTE: The radius of Earth is 3960 miles.

2007-09-10 10:09:01 · 3 answers · asked by journey 1

A plane leave a certain airport from runway 4 RIGHT, whose bearing is N40degreesE. After flying for 1/2 mile, the pilot requestd permission to trun 90 degrees and head toward the southeast. The permission is granted. After the airplane goes 1 mile in this direction, what bearing should the control tower use to locate the plane?

After my work, I got S23.4degreesE but the book's answer is
S76.6degreesE.

How do I get the book's answer? Why is my answer wrong?

2007-09-10 10:01:21 · 2 answers · asked by journey 1

How do you find a physics formula from a table of values? I can only do it with Excel ... Like how can you tell when to use y=1/x^3 instead of y=1/x^2, when the graphs look extremely similar? For example, I will type 2 data tables.
_________
A B
2 100
8 200
50 500
200 1000
--------------

____________
E F
2 90
54 270
16 180
250 450
--------------

The first table is square root while the second is cubed root, but when I graphed them, they looked almost exactly the same ...

2007-09-10 09:57:36 · 3 answers · asked by Anonymous

My teacher asked us to research the meaning of a formula. I don't know how to type it up into google or anything so I was hoping someone can help me.
http://i5.photobucket.com/albums/y162/MuffinMilk/formuala.jpg
^that's the formula, i had to write it and then scan it
please + thank you.

2007-09-10 09:56:48 · 3 answers · asked by emitothelee 1

2007-09-10 09:52:14 · 5 answers · asked by Anonymous

aristotle believed wood was a combination of fire, water, and earth. use his four-elements theory to explain why a wooden boat floats on water.

2007-09-10 09:46:29 · 19 answers · asked by alhan 1

2007-09-10 09:43:07 · 10 answers · asked by Anonymous

2007-09-10 09:37:02 · 5 answers · asked by alhan 1

A car sits in an entrance ramp to a freeway, waiting for a break in the traffic. The driver sees a small gap between a van and an 18-wheel truck and accelerates with constant acceleration along the ramp and onto the freeway. The car starts from rest, moves in a straight line, and has a speed of 10 m/s (22 mi/h) when it reaches the end of the 115 m long ramp.

(a) What is the acceleration of the car?
m/s2
(b) How much time does it take the car to travel the length of the ramp?
seconds
(c) The traffic on the freeway is moving at a constant speed of 10 m/s. What distance does the traffic travel while the car is moving the length of the ramp?
meters

2007-09-10 09:33:30 · 1 answers · asked by Walachka 3

My teacher went over this stuff so fast, I couldn't get all of the notes. The question is this:

Using the concepts of force, impulse and time (F*t), briefly explain why an airbag is a beneficial safety feature.

I need to understand this stuff for our test next week. There's no textbook for this source and it's a lecture hall course, so office hours for my professor are pretty filled up. Can someone explain this to me?

Thanks

2007-09-10 09:16:53 · 4 answers · asked by seventhyearfalling 2

Three forces, A, B, and C, acting together, produce a resultant force of 10 N in the +y direction.

Force A is 10 N in the +y direction.
Force B is 10 N in the -y direction.

What is the magnitude and direction of force C?
Solve by the method of components.

(I don't even know where to begin! Any help would be appreciated!)
Thanks :)

2007-09-10 09:12:15 · 3 answers · asked by Anonymous

A basketball player, standing near the basket to grab a rebound, jumps 76.0 cm vertically. How much total time does the player spend (a) in the top 15.0 cm of this jump and (b) in the bottom 15.0 cm? Does this help explain why such players seem to hang in the air at the tops of their jumps? Show and explain your work. Thanks and good luck! :)

2007-09-10 09:10:43 · 1 answers · asked by Anonymous

we know that there is a valence band, forbidden band and a conduction band of electrons for an atom. For conduction to take place electrons in the valence band need to gain energy and jump to the conduction band.

but say for pure silicon can an electron exist in the forbidden band?
how about for doped silicon?

2007-09-10 08:22:04 · 1 answers · asked by sh 1

Imagine you and a friend are standing on the equator, 90 degrees apart, with you in Kansas and your friend near Hawaii. You both start walking in a straight line, north.

You notice that the further north you go, the closer you and your friend are. Its as if there is a force acting between you two, pulling you two together.

Is there really a need for a force carrying particle (a graviton I think its called) to attract 2 bodies? So why do they think there is one, other than it being a cosmetic issue for the standard model? Same goes for looking for gravity waves.

2007-09-10 08:06:46 · 4 answers · asked by Anonymous

1) 440 m/s
2) 4400 m/s
3) 44 m/s
4) 4.4 m/s
(cp / cv=Gamma=1.4)

Please show me ... how to solve

2007-09-10 07:42:35 · 4 answers · asked by Anonymous

Suppose also that the protons are placed at the Earth's North Pole and the electrons are placed at the South Pole. What is the resulting compressional force on the Earth?
The answer should be in Newtons

2007-09-10 07:28:40 · 3 answers · asked by ferrari2388 1

energy by way of wind force while driving a car? Could you somehow use small wid turbines to run your engine after enough speed.? Is there any one trying to do this sort of thing?

2007-09-10 07:22:18 · 5 answers · asked by Anonymous

A firefighter with a weight of 712 N slides down a vertical pole with an acceleration of 3.00 m/s^2, directed downward. What are the magnitudes and directions of the vertical forces (a) on the firefighter from the pole and (b) on the pole from the firefighter? Show your work and good luck. Thanks!

2007-09-10 07:12:28 · 1 answers · asked by Anonymous

1. A helicopter blade is designed to rotate at such an angular velocity that the tip of the blade is less than the speed of sound in air, which is 340 ms-1. The blades rotate at 260 r.p.m Calculate the maximum possible length of the blades.

2. A Cd player varies the rate of rotation of the dics in order to keep the track from which the music is being reproduced moving at a constant linear speed of 1.30ms-1. Clacutae the rates of rotation of a 12.0 cm disc when the music is being read from
(a) the outer edge of the disc
(b) a point 2.55cm from the centre of the disc.
Give answers in rads-1 and in rev min-1

2007-09-10 06:55:39 · 2 answers · asked by Anonymous

give an example of a situation in which you would use a Schottky diode(as a discrete device).

What are the advantages in this situation?

2007-09-10 06:46:14 · 2 answers · asked by sh 1

Give an example each of a semiconductor material that can produce red, green, and blue LEDs

2007-09-10 06:45:07 · 1 answers · asked by sh 1

Compare the acceleration on stopping with the acceleration of gravity.

2007-09-10 05:45:28 · 5 answers · asked by Anonymous

Two forces act on a 3.1 kg mass, which undergoes acceleration a = 0.93 i - 0.22 j m/s2. If one of the forces is F1 = - 1.0 i - 2.9 j N, what is the other force?

2007-09-10 04:51:43 · 2 answers · asked by wil 1

2007-09-10 02:59:38 · 11 answers · asked by Abdulrasheed S 1