Physics - February 2007

Cannon is aimed right at the target located d = 1200m due north
from the cannon and fired. Initial speed of the ball v = 200m/s,
angle of inclination α = 15 degrees to the horizon. The ball misses
the target by r = 40m to due east, because gunmen did not
take into account the wind blowing from due west with the
speed u = 12 m/s.

How much time did the cannon ball spend in the air?


Since it is fifth repost a hint would be appropriate:
There exists a frame of reference where
the force of gravity, the force of air resistance,
and velocity of the ball are all co-planar.

2007-02-28 04:59:07 · 3 answers · asked by Alexander 6

An electron with charge q=-1.6x10-19C and mass 9.11x10-31kg moving at speed v enters into a region where the uniform magnetic field B=3.4x10-4 bends the pathy of the electron in to a semicircle with radius .041m?
1.What is the speed as it enters the region of nonzero magnetic field? ( I know sin of angle =1, and F=ma, and F=qvB to then solve for v....but i don't know what "a" is in F=ma)
2.What is the speed as it leaves the region of nonzero magnetic field? (I think this is the same as #1 b/c magnetic field can only change the direction, not the speed)
THANKS SO MUCH IN ADVANCE!

2007-02-28 04:55:47 · 1 answers · asked by Anonymous

An Air Bubble released from a diver's breathing apparatus at a depth of 40 m has a diameter of 2.0. When it reaches the surface of the water it has a diameter of 3.4 cm.

Show that the volume of the air bubble has increased by a factor of Approx 5.

This is NOT! My homework!

2007-02-28 04:52:30 · 4 answers · asked by Miss LaStrange 5

A charged particle hurtles through space, creating its own magnetic field. If it strikes the earth's magnetic field at the equator, the two magnetic fields interact and _______.

A) do not affect the particles direction

B) change the particle's speed but not its direction

C) change the particle's speed and direction

D) change only the particle's direction

E) bounce it back in the direction it came from

2007-02-28 04:36:20 · 3 answers · asked by nando 1

2007-02-28 04:26:18 · 8 answers · asked by Anonymous

A) the moving current causes no magnetic field

B) the moving current causes a magnetic field

C) increasing the current increases the magnetic field

D) increasing the current decreases the magnetic field

E) both B and C

2007-02-28 04:17:41 · 2 answers · asked by nando 1

A) north poles

B) south poles

C) the same poles

D) opposite poles

E) no polarity

2007-02-28 04:05:08 · 6 answers · asked by nando 1

2007-02-28 03:30:24 · 21 answers · asked by evilchass2004 2

CAREFUL MEASUREMENTS SHOW THAT THERE IS ___.

A) a continuous current in the wire

B) an electric current in the wire only when the wire is moving

C) no electric current in the wire

D) an electric current in the wire only when the wire isn't moving

E) none of the above

2007-02-28 03:25:33 · 5 answers · asked by max 1

2007-02-28 03:17:12 · 1 answers · asked by siMpLy 2

an alternative materials that can be used as resistors? can somebody help me?

2007-02-28 03:01:39 · 8 answers · asked by niere28 1

2007-02-28 02:48:45 · 2 answers · asked by Anonymous

A) movement of magnetic poles

B) the product of current times resistance

C) resistance to the passage of electrical charges

D) movement of electrical charges

E) movement of atoms in a solid

2007-02-28 02:23:23 · 6 answers · asked by Max 1

I have heard speculation that this happened and proves that micro-black holes can pop in and out of existence at anytime. Possibly Wimbledon in 1976.

2007-02-28 02:15:36 · 7 answers · asked by Mont M 4

if not could you do it now and tell me what happens?

2007-02-28 02:12:01 · 8 answers · asked by youngie 2

A) free electrons move toward positive charges

B) free electrons move toward negative charges

C) free protons move toward negative charges

D) free protons move toward positive charges

E) neither protons nor electrons are free to move

2007-02-28 02:11:59 · 2 answers · asked by Max 1

So i'm kind of obsessive about researching. You might remember Antimatter from Star Trek, it is what fueled the ships. It is when Matter & Antimatter collide it would annihilate everything, the same as nuclear explosion. If there were to be antimatter on this earth it would inevitably come into contact with matter & we would be completely destroyed. Antihydrogen is a stable antimatter, but we arent able to test all of it's theoretical properties. In the 1990's we found ways to create artificial products of atoms of antimatter(antihydrogen). A single atom of antihydrogen is made up of a -charged antiproton being orbited by a +charged positron. Have you heard of positron weaponry? A type of antimatter weaponry. It would leave behind "no nuclear residue". Scientists say there's no way to make antimatter bombs because they do not store energy. But the government is still funding for researchers to find a way to store positrons for long periods. What do you think, antimatter weaponry?

2007-02-28 02:05:09 · 7 answers · asked by Anonymous

When mass M is at the position shown, it is sliding down the inclined part of a slide at a speed of 2.41 m/s. The mass stops a distance S2 = 1.9 m along the level part of the slide. The distance S1 = 1.07 m and the angle q = 33.30°. Calculate the coefficient of kinetic friction for the mass on the surface.

2007-02-28 02:04:21 · 3 answers · asked by bud 1

For me, i can imagine that each and everyone of us will be floating in the air. The things around us will also react the way we do. But really want to know how it feels when there is no gravity on earth or try it out in the moon if you or i have the chance.

2007-02-28 02:03:04 · 12 answers · asked by lin shuji 1

Battery terminals placed in a weak acid cause positive charges to flow in one direction and negative charges to flow in other direction. This flow of charged particles is called____.

A) a conductor

B) an insulator

C) shocking

D) current

E) resistance

2007-02-28 02:02:23 · 4 answers · asked by Max 1

What happens if water changes phase?

2007-02-28 01:58:29 · 4 answers · asked by Anonymous

A) attraction gets larger

B) attraction remains the same

C) attraction gets smaller

D) repulsion gets larger

E) repulsion gets smaller

2007-02-28 01:53:09 · 5 answers · asked by Max 1

Could it be possible, in accordance with Einstein's Theory of Relativity, that light actually bends as it heads towards inifinity and that all matter (a person for exmple) in a frame parallel to that light also bend at the same rate so that light appears (in a sterile vacuum) to head in infinitely straight path. Is this a plausible theory? Please cite relevelant published theories to back up your answer. Thank you for your time and help.

2007-02-28 01:44:23 · 4 answers · asked by kimchinamja 1

As two attracting charges are brought together, the size of the force between them _____ as the distance between them gets smaller.

A) increases rapidly

B) increases slightly

C) remains unchanged

D) decreases slightly

E) decreases rapidly

2007-02-28 01:41:58 · 2 answers · asked by Max 1

Mixing a 10% acid solution with a 15% acid solution, how many milliliters of the 10% solution would be needed to produce a 1500 milliliter solution of 12% acid?

2007-02-28 01:22:45 · 3 answers · asked by RegularGuy 2

Won't the object just remain stationary?
[This is about Resultant Force...]
Please offer more detailed explanations...Thank you =)

2007-02-28 01:19:09 · 3 answers · asked by Anonymous

Such as Origin of low temperature and pressure,different kinds,properties,physics in different fields,applications,Recent trends in that field,Developement in India And in abroad.

2007-02-28 01:12:20 · 3 answers · asked by Nagabhushan b 1

2007-02-28 01:12:14 · 4 answers · asked by Raccch 1

2007-02-28 01:07:21 · 22 answers · asked by ~* The BookWorm *~ 2

2007-02-28 00:45:39 · 13 answers · asked by Arun 2