Physics - September 2007

A ball is thrown up in the air with a velocity of 35m/s. (Assume the ball starts with an initial height of 2m)
At what time is it at an altitude of 1.0 meters above the ground? (Use the quadratic formula)

2007-09-20 16:46:18 · 2 answers · asked by sam 2

a projectile is fired with an initial speed 75.2 m/s at an angle of 34.5 above the horizontal on a long flat firing range. a)determine the maxim height reached by the projectile
b) the total time in the air (forget this one)
c) the total horizontal distance covered (that is, the range)
d) the veolcity of the projectile 1.5s after firing


please helpp step by step procedure on doing this =(

2007-09-20 16:36:48 · 5 answers · asked by LilChineseFob 1

It's been like that all $#@% day!!!

2007-09-20 15:57:33 · 1 answers · asked by Anonymous

An accelerometer ( a device to measure acceleration) can be as simple as a small pendulum. Suppose you are flying a small plane in a straight horizontal line and your accelerometer hangs 12 degrees behind the vertical. What is your acceleration?

2007-09-20 15:53:39 · 2 answers · asked by triciawin87 2

Can somebody break this down for me step by step so I can learn how to do it?

A major league pitcher can throw a baseball in excess of 41.1 m/s. if a ball is thrown horizontally at this speed, how much will it drop by the time it reaches the catcher who is 17.6 m away from the point of release?

2007-09-20 15:52:09 · 4 answers · asked by yummy_girlscout 1

in space...or anywhere else, is there such thing as "dark matter"? like a thing of darkness that you can have in a jar or hold in your hand????

2007-09-20 15:51:43 · 3 answers · asked by Anonymous

A rocket used to lift a satellite into orbit undergoes a constant acceleration of 6.25 m/s^2. When the rocket reaches an altitude of 45 km above the surface of Earth, it is traveling at a velocity of 625 m/s. How long does it take for the rocket to reach this speed? Show your work. I really need this tonight, but I'll check this super early in the morning. If anyone knows, please help....thanks a lot!

2007-09-20 15:44:42 · 2 answers · asked by ☺♠JonasJay♫♦ 5

A new car manufacturer advertises that their car can go "from zero to sixty in 8 s". This is a description of

a. average speed.
b. instantaneous speed.
c. average acceleration.
d. instantaneous acceleration.

2007-09-20 15:26:18 · 1 answers · asked by ME 1

2007-09-20 15:14:13 · 3 answers · asked by Anonymous

A 770 kg car, with a 95 kg driver, is driving up a shallow hill of angle θ = 5° directly
into a strong headwind. The headwind exerts a force 200 N on the car. The coefficient of
rolling friction for the car on the road is 0.025. What force must the car’s engine produce
so that it travels at a constant velocity of 10 m/s.

2007-09-20 15:05:05 · 1 answers · asked by Dave D 1

A steel ball is 4.000cm in diameter at 28C. A brass ring has an interior diameter of 2.992cm at 30C. At what common temperature will the ball just slide through the ring?

2007-09-20 15:03:10 · 1 answers · asked by Jeena B 1

A rocket moves upward, starting from rest with an acceleration of 30 m/s2 for 2.5 seconds. It runs out of fuel at the end of the 2.5 seconds but doesn't stop. How high does it rise above the ground?

2007-09-20 15:00:55 · 1 answers · asked by thepolishway 3

Why does a closed, empty, 2-L, plastic soft-drink bottle cave in when placed in a freezer?

2007-09-20 14:48:51 · 2 answers · asked by JustAnotherMarionette. 6

2007-09-20 14:46:41 · 2 answers · asked by ohhsnap! 4

Can you explain why they are alike and if not why they aren't

2007-09-20 14:44:33 · 6 answers · asked by Lakers24 2

What is the wavelength of electromagnetic radiation that has a frequency of 3 x 10 (to the 16th power) Hz? In what part of the spectrum does this radiation occur?

2007-09-20 14:44:01 · 2 answers · asked by New Mommy 1

A box with a mass of 20 kg, slides a ramp with an acceleration of 0.4 m/s2. The ramp is at an angle θ = 10°. What is the force of friction and coefficient of dynamic friction, μk, between the box and the ramp.
(I don't understand non-equilibrium questions)

2007-09-20 14:42:41 · 3 answers · asked by Laduch 2

A space vehicle accelerates uniformly from 65m/s at t=0 to 162m/s at t=10.0s. How far did it move between t=2.0s and t=6.0s?

I'm having problems on how to find the positions for 2.0s and 6.0s.

2007-09-20 14:04:37 · 1 answers · asked by Mimi 1

I know this should be separated into 2 problems in order to solve it. but I've been stuck on where to start, so help. Please?

An inattentive driver is traveling 18.0m/s when he notices a red light ahead. His car is capable of decelerating at a rate of 3.65m/s^2. If it takes him .200s to get the brakes on and he is 20.0m from the intersection when he sees the light, will he be able to stop in time?

2007-09-20 14:00:55 · 4 answers · asked by Mimi 1

Lately I have found everything about space to be absolutely fascinating. It just occured to me that the farther from the sun we travel gravity changes and so does time, but the physics that control these variables always stays the same. Or at least thats how it seems from my prespective.

Now I understand that we are about 20 years or so, as predicted by NASA from passing through the heliopause or the boundry line of where intersteller space begins.

Now to my knowledge, intersteller space is defined as being matter, or space that is taken over by other stars solar winds and other energies.

Once this boundry is crossed, do you think our understanding of todays physics will break down?

What are the possibilities if we could reach a galaxy with completely different physics than out own?

I hope that I have explained my question good enough for everyone to understand what I am asking. Space and intersteller space is mind boggling!

2007-09-20 13:59:42 · 4 answers · asked by Anonymous

I need to know how i should go about handling a collision.
I can detect that the collision has occured, but by stopping the player completly normaly means it looks bad or i get stuck on the object. I need to know how to go about making it Slide across the surface when it collides on a angle, using the objects Vector3 Position, Vector3 Velocity ect...

2007-09-20 13:53:29 · 1 answers · asked by Anonymous

Have a friend hold a ruler by one end, letting the other end hang down vertically. At the lower end, hold your thumb and index finger on either side of the ruler, ready to grip it. Have your friend release the ruler without warning. Catch it as quickly as you can. If you catch the ruler 6.8 cm (~2.7 inches) from the lower end, what is your reaction time?

2007-09-20 13:47:34 · 1 answers · asked by Sanyok 1

V/d = E

I know d is distance, but what are V and E? Energy and voltage?

2007-09-20 13:25:20 · 2 answers · asked by Curious 1

three ballot boxes are connected by cords, one of which wraps over a pulley having negligible friction on its axle and negligible mass. The masses are mA = 27.0 kg, mB = 42.0 kg, and mC = 13.0 kg. When the assembly is released from rest, (a) what is the tension in the cord connecting B and C, and (b) how far does A move in the first 0.290 s (assuming it does not reach the pulley)?

2007-09-20 13:23:33 · 1 answers · asked by Samuel Tewolde 1

A ball is thrown vertically upward (assumed to be the positive direction) with a speed of 16.0 m/s from a height of 3.0 m.
(a) How high does the ball rise from its original position?
m
(c) How long does the ball take to hit the ground after it reaches its highest point?
s

2007-09-20 12:53:32 · 1 answers · asked by NiNi 2

A boat takes 2.70 hours to travel 35.0 km down a river, then 5.90 hours to return. How fast is the river flowing?

2007-09-20 12:42:45 · 1 answers · asked by Anonymous

2) rocket powered sleds are used to test the responses of himans to acceleration. Starting from rest, one sled can reach a speed of 444m/s in 1.80s and can be brought to a stop again in 2.15s.

a) calculate the acceleration of the sled when starting and compare it to the acceleration due to gravity, 9.80m/s^2.

b) Find the acceleration of the sledwhen braking and compare it to the magnitude of the acceleration due to gravity.

If you answer all questions, I would be very pleased and give you 10 free points thank you for solving the hard questions

2007-09-20 12:42:12 · 1 answers · asked by Anonymous

we did a lab where you time how long it takes for a cart to roll down a plank of wood at difference angles.

1. What are 3 sources of error?
2. What is the cause of the most error?
3. How does friction change with increased angle?
4. Is the acceleration (without friction) uniform?


any help will be VERY MUCH appreciated. THANK YOU!

2007-09-20 12:24:10 · 3 answers · asked by brubabe 5

what is mass? how are some ways that it can be measured?

2007-09-20 12:08:49 · 7 answers · asked by Sarah S 3

what is the velocity when the wrench strikes the ground?

could you tell me which formula to use (acceleration, velocity, or displacement?)

I dont understand what the variables are or which formula to use. please explain!! Thanx

2007-09-20 12:03:50 · 5 answers · asked by Smiley 3