Physics - September 2007

CHOICES
a. air resistance
b. its own speed
c. gravity
d. speed of the wind

If you have an answer please give the reason!!
thanks!!!

2007-09-04 01:19:52 · 7 answers · asked by Anonymous

2007-09-04 01:14:43 · 13 answers · asked by Anonymous

What is the energy conversion that occurs when alpha, beta particles and gamma rays are emitted?
Is it true that alpha and beta particles possess kinetic energy while the gamma rays don't?
It would be very helpful if you could help me with this.

2007-09-04 01:06:55 · 1 answers · asked by Anonymous

of the beam. A string is attached to the mid-point of the beam and to the wall at a point B on the wall (B is metres about A) so that the string is horizontal.

How do I calculate the tension in the string?

2007-09-04 01:05:33 · 4 answers · asked by Anonymous

2007-09-04 00:06:49 · 5 answers · asked by robert 1

we have a group project in physics... we're supposed to make a racing car using a mouse trap... it's almost done, we will just design it and it's alright.. but our problem is it won't travel that long... it only goes until the length of a table... and we will have a racing competition using it... sometimes it's not working, it's not running... what should we do with the mouse trap to make it work?? please help... our deadline is on friday, we have only 3 days left...

2007-09-03 23:01:35 · 1 answers · asked by Anonymous

2007-09-03 20:09:35 · 6 answers · asked by Zheng Rong 1

what could be the reason for this tunnels in round shape ? is it related to any gravitaional force ? please answer me. thanks in advance

2007-09-03 19:48:59 · 2 answers · asked by Ramesh.V V 1

air craft has a lift off speed of 120 km/h
one dimensional motion with constant accel

2007-09-03 17:35:02 · 1 answers · asked by doggydawg 1

The Beretta Model 92S (the standard-issue U.S. army pistol) has a barrel 127 mm long. The bullets leave this barrel with a muzzle velocity of 335 m/s .
What is the acceleration of the bullet while it is in the barrel, assuming it to be constant? Express your answer in m/s2 .
I don't know how to get the answer in m/s2, can anybody help me?

2007-09-03 16:52:21 · 1 answers · asked by osu9295 1

Kathy Kool buys a sports car that can accelerate at the rate of 4.70 m/s2. She decides to test the car by dragging with another speedster, Stan Speedy. Both start from rest, but experienced Stan leaves the starting line 1.00 s before Kathy. Stan moves with a constant acceleration of 3.80 m/s2, and Kathy maintains an acceleration of 4.70 m/s2.
(a) Find the time it takes Kathy to overtake Stan.
s
(b) Find the distance she travels before she catches him.
m
(c) Find the speeds of both cars at the instant she overtakes him.
Kathy
m/s
Stan
m/s

2007-09-03 16:13:21 · 1 answers · asked by justin l 1

1). A motorist is traveling at 18.2 m/s when he sees a deer in the road 38.1 m ahead.

(a) If the maximum negative acceleration of the vehicle is -4.50 m/s2, what is the maximum reaction time t of the motorist that will allow him to avoid hitting the deer?
s
(b) If his reaction time is actually 0.300 s, how fast will he be traveling when he hits the deer?
m/s

2)An inquisitive physics student and mountain climber climbs a 50.0 m cliff that overhangs a calm pool of water. He throws two stones vertically downward, 1.00 s apart, and observes that they cause a single splash. The first stone has an initial speed of 2.00 m/s.
(a) How long after release of the first stone do the two stones hit the water?
s
(b) What was the initial velocity of the second stone?
m/s (downward)
(c) What is the velocity of each stone at the instant the two hit the water?
first stone
m/s (downward)
second stone
m/s (downward)

2007-09-03 16:10:27 · 1 answers · asked by justin l 1

O.k. I know that like gravity is when two molecules like attract to each other. And the more the mass, the more gravity. But what is gravity? Like what causes it? I'm just real puzzled here. Somebody help me!

2007-09-03 15:39:00 · 10 answers · asked by Hoopsta 22 2

of the point of release projectile?

a. (0 , x)
b. (range , zero)
c. (zero , range)
d. (y, 0)

2007-09-03 15:32:49 · 1 answers · asked by Jason B 1

2007-09-03 14:48:49 · 4 answers · asked by Aileen b 1

For a particular set of measurements it turns out that when the velocity is plotted on the vertical axis, and the acceleration is plotted on the horizontal axis, the result is a straight line. When a "slope triangle" is drawn for these data, it is found that the rise is 2.5 m/s, and the run is 3.2 m/s2. Which of the following is the slope?

Lab help. I have spent an hour on it and I can't figure it out.

These are the possible answers:

1.28 m2/s3
0.781 m2/s3
8.00 s
0.781/s
1.28 s
1.28/s
8.00 m2/s3
0.781 s
8.00/s

2007-09-03 14:36:52 · 2 answers · asked by lstntht 1

OK, we know that atoms are made up of electrons, neutrons, and protons. What is the space that the electrons float in? Other than a 'cloud'.

2007-09-03 14:36:34 · 4 answers · asked by homeskoolmama 1

I am trying to find an equation for the time it takes for a transverse wave to travel from one end to the other of a string with two fixed points.

The known values are Tension (T), mass of string (m), lenghth of string (L), and wave speed (v).

thanks for the help anyone

2007-09-03 14:29:16 · 2 answers · asked by snoboarder2k6 3

2007-09-03 14:19:30 · 5 answers · asked by Anonymous

Suppose that a large mixing tank initially holds 300 gallons of water in which 50 pounds of salt have been dissolved. Another brine solution is pumped into the tank at a rate of 3 gal/min, and when the solution is well stirred, it is then pumped out at a Slower Rate of 2 gal/min. If the concentration of the solution entering is 2lb/gal, determine a differential equation for the amount of salt A(t) in the tank at time t.

2007-09-03 13:52:42 · 1 answers · asked by rika 3

2007-09-03 13:42:10 · 6 answers · asked by ? 6

"The phrase refers to the idea that a butterfly's wings might create tiny changes in the atmosphere that ultimately cause a tornado to appear (or prevent a tornado from appearing). The flapping wing represents a small change in the initial condition of the system, which causes a chain of events leading to large-scale phenomena. Had the butterfly not flapped its wings, the trajectory of the system might have been vastly different"

I gotta say, it seems possible.

2007-09-03 13:33:52 · 9 answers · asked by Metsfan666 2

2007-09-03 13:28:33 · 1 answers · asked by Me 1

You are arguing over a cell phone while trailing an unmarked police car by 25m; both your car and the police car are traveling at 110km/h. Your argument diverts your attention from the police car for 2.0s (long enough for you to look at the phone and yell, "I won't do that!"). At the beginning of that 2.0s, the police officer begins braking suddenly at 5.0m/s2. (a) What is the separation between the two cars when your attention finally returns? Suppose that you take another 0.40s to realize your danger and begin braking. (b) If you too brake at 5.0 m/s2, what is your speed when you hit the police car?

2007-09-03 12:50:23 · 1 answers · asked by Anonymous

the rubber worn from tires mostly enter atmosphre as pollution. Estimate how much rubber (kg) is put into the air in US every year. An estimate for a tire tread's depth is 1 cm when new and the density of rubber is about 1200 kg/m^3

2007-09-03 12:30:01 · 1 answers · asked by Anonymous

A small 12.00g plastic ball is suspended by a string in a uniform, horizontal electric field with a magnitude of 103 N/C. If the ball is in equilibrium when the string makes a 30 angle with the vertical, what is the net charge on the ball?

2007-09-03 12:23:12 · 1 answers · asked by Anonymous

started to move faster than average or slower than average? Why do molecules have a tendancy to move and why cant they stop? Would life sese to exist if molecules reached absolute zero motion?

2007-09-03 12:03:42 · 4 answers · asked by Anonymous

Planes flying east - west travel at about the same speed as planes flying west - east (ignoring the wind factor). Why doesn't the Earth's rotation make more difference?

2007-09-03 11:33:28 · 7 answers · asked by Anonymous

2007-09-03 11:15:10 · 1 answers · asked by Nikita 1

Is there a fourth dimension? If so, is the fourth dimension the spirit world as taught in the Bible?

What does physics teach about a dimension beyond the third?

2007-09-03 11:10:34 · 6 answers · asked by Anonymous