Physics - May 2007

A .20 kg pinecone falls from a branch 18m above the ground.
(a) With what speed would it hit the ground if air resistance could be ignored?
(b) if it actually hits the ground with a speed of 10 m/s, what was the average force of air resistance exerted on it?

2007-05-21 18:16:04 · 5 answers · asked by Tech19 3

A man claims that a powerful radio antenna next to his land caused sparks to jump across the wires in a fence gate, and onto his sheep, killing it.
I am given frequency and the length of each piece of wire on the gate.
Why is this a highly unlikely situation, for the sheep to be killed?

2007-05-21 18:01:55 · 7 answers · asked by spiffy_mcbang13 1

I'm making a mousetrap car. I need an axle for the wheels. I looked at Home depot and Lowes and searched axles, but nothing comes up. What should I search, and what are they called?

2007-05-21 17:56:32 · 5 answers · asked by sh0ty_m5@sbcglobal.net 2

If anyone can help me out with this I would really appreciate it. I can not come up with the right answer that's in the book. Thank you :D

An airplane is flying through a thunderstorm at a height of 2100 m. (This is a dangerous thing to do because of updrafts, turbulence, and the possibility of electric discharge.) If there are charge concentrations of +40.0 C at a height of 3700 m withiin the cloud and -40.0 C at a height of 1000 m, what is the electric field E at the aircraft? (Give the magnitude and direction.)

2007-05-21 17:25:14 · 2 answers · asked by Michelle 1

this is my worst subject. and if you could please give good explaination on how to solve the problem? --thanks

A 5.00 x 10^2 kg object is attached by a rope through a pulley to a paddle-wheel shaft that is placed in a well-insulated tank holding 25.0 kg of water. the object is allowed to fall, causing the paddle wheel to rotate, churning the water. if the object falls a vertical distance of 1.00 x 10^2 m at constant speed, what is the temperature change of the water? (cp= 4186 j/kg C and g= 9.81 m/s^2)

2007-05-21 16:59:22 · 3 answers · asked by itink3 1

2007-05-21 16:38:30 · 12 answers · asked by Goddess 1

2007-05-21 16:21:47 · 3 answers · asked by neena m 1

2007-05-21 16:06:36 · 6 answers · asked by neena m 1

2007-05-21 16:04:58 · 8 answers · asked by neena m 1

Please help and give an answer as soon as possible?!?!

2007-05-21 15:59:14 · 3 answers · asked by Ashley 1

i mean on the van de grraff machinery ...the motor nd all

2007-05-21 15:53:22 · 1 answers · asked by Anonymous

How much energy is there? And why is the sum positive (if it is)? What is going on?

2007-05-21 13:57:47 · 4 answers · asked by Ejsenstejn 2

What is the work done on an object that moves for 12m with a 200N force acting on it

2007-05-21 12:49:12 · 5 answers · asked by Anonymous

so...um...yea....is it a centripetal force?

2007-05-21 12:47:08 · 9 answers · asked by KiWiMeLoN 2

if i have 2 points, in this case (1,2,6) and (-2,-1,3) and a line passing through them, how do i find the direction this line is going?

2007-05-21 12:39:18 · 2 answers · asked by fpa06mr 5

The yo-yo has a mass of .2kg and is attached to a sting .8 m long. If the yo-yo makes a complete circular revolution each second, what tension must exist in the string? Can anyone please show me how to do this. thanks.

2007-05-21 11:03:42 · 2 answers · asked by w_xsoadx_w 2

Currently doing a lab but these angles are not equal?

2007-05-21 11:02:37 · 4 answers · asked by clashinggrandeur 1

i read that in november there will be some huge experiment, the biggest ever, happening in november this year to look at what particles are made in a collision. protons will be sent in different directions at high speed round the circumference of a hole as i understand so they collide. apparently it will look at creating mini black holes which will give more information on how the universe was originally created. anyone else heard anything of it? i am so confused!! xxx

2007-05-21 10:52:17 · 3 answers · asked by Anonymous

transfers happen? i couldnt figure it out and i need some help:(

2007-05-21 10:50:49 · 3 answers · asked by hello 1

2007-05-21 10:29:59 · 8 answers · asked by Jeremy 2

2007-05-21 10:28:33 · 15 answers · asked by Anonymous

if a boy is drinking milk by a straw from a glass. p1 is the pressure at bottom of the glass p2 at the surface and p3 in the mouth then:
1)p3 is less than p1
2)p2 is less than p1
3)none

Please explain!!!!!!!!!!!!!!!!!!!!!

2007-05-21 09:54:47 · 3 answers · asked by SadGirl$ 2

2007-05-21 09:41:15 · 10 answers · asked by Anonymous

For each of the following, decide which forms of energy are present: a leaf falls from a tree; a candle burns; a rubber band is wrapped around a newspaper.

A roller coaster car with a mass of 500 kg is at the top of a hill that is 30 m high. Without friction, what would its kinetic energy be as it reached the bottom of the hill?

How does heat differ from thermal energy?

2007-05-21 09:38:25 · 5 answers · asked by maosportz 2

2007-05-21 09:36:54 · 7 answers · asked by Anonymous

If one keeps a guitar in the closet and plays it only every few months, the sound is not as warm or resonant as daily playing.

Playing often could prevent rusting of the strings. BUt i have observed the same thing with nylon-string guitars too. Perhaps its something to do with the wood ? Or maybe playing often keeps dust buildup away from where the strings contact the bridge and neck, and so help the strings vibrate more ?

2007-05-21 09:30:37 · 4 answers · asked by martes 1

Recently wondered why, so decided to ask you lot :)

2007-05-21 09:19:38 · 8 answers · asked by Anonymous

Ratio between two different quantites

Property of a body that resists any change in velocity

mass of an object multiplied by its velocity

upward force of air agianst a moving object

velocity in an up or down direction

unit of measurment for force

a push or pull exerted on one body by another

forces always come in ___

two objects with the same velocity must be moving in the same __

a force that acts on all objects on earth

the force that opposes the motion of two touching surfaces

the amount of force per unit area

2007-05-21 09:15:16 · 3 answers · asked by Anonymous

help I am lost :(

2007-05-21 08:44:27 · 4 answers · asked by Eric 1

What is the power used by the toaster?


help I am lost :(

2007-05-21 08:42:32 · 5 answers · asked by Eric 1