Physics - February 2007

2007-02-14 14:06:07 · 9 answers · asked by Anonymous

Hi. I'm doing an experiment that involves measuring dynamic viscosity at different temperatures. The formula for calculating viscosity requires that I use the density of the liquid I'm using (which are water and pure ethanol). The range of temperatures is -10 degrees to 30 degrees C; will the varying density of liquids differ by more than 2 significant figures for the two liquids listed?

2007-02-14 13:54:56 · 1 answers · asked by J Z 4

A helicopter is ascending vertically with a speed of 6.00m/s. At a height of 115m above the Earth, a package is droppped from a window. [Hint: The package's initial speed equals the helicopter's.]

2007-02-14 13:47:06 · 4 answers · asked by Vanita L 1

The process of changing the frequency or amplitude of radio waves in order to encode a signal is
a. diffraction.
b. modulation.
c. reflection.
d. refraction.

2007-02-14 13:44:49 · 2 answers · asked by johnnycash b 1

Any ideas just show me how.

2007-02-14 13:42:52 · 2 answers · asked by Anonymous

A sports car moving at constant speed travels 90m in 4.9s. If it then brakes and comes to a stop in 4.0s. Express the answer in terms of g's, where g= 9.8m/s^s
I tried this question and got 0.47g, but it was incorrect.

2007-02-14 13:42:47 · 3 answers · asked by Vanita L 1

When light enters matter,
a. it can slow down or speed up.
b. stops.
c. travels at 300 000 km/s.
d. travels at the speed of sound.

Is it A?

2007-02-14 13:41:56 · 1 answers · asked by johnnycash b 1

why? i need help asap

2007-02-14 13:38:32 · 2 answers · asked by blahhhhhh 2

why & how?

2007-02-14 13:23:24 · 8 answers · asked by Aleta F 1

A very shallow pond contains 1.50 x 10^5 kg of water at 23°C. At the end of a windy day, 1.00 x 10^3 kg of water was lost by evaporation. It takes 2.26 x 10^6 for 1 kg of water to evaporate.

1. How much energy was removed from the pond by heat of evaporation? (Do you use the Q = mcΔT formula?)
2. How much water was left in the pond? (I just don't know how to this one)
3. By how much did the temperature of the water drop in the pond?(Do you use the Q = mcΔT formula, where c = 4.19 x 10^3 J/kg C°)
4. Assuming there were no other changes in energy, what was the temperature of the water at the end of the day? (Which formula do I use?)

Thank you!!

2007-02-14 12:56:48 · 1 answers · asked by Anonymous

2007-02-14 12:54:25 · 3 answers · asked by horses1193 1

2007-02-14 12:53:05 · 5 answers · asked by ♫♪♫ PINKY ♫♪♫ 5

2007-02-14 12:37:29 · 3 answers · asked by Christina T 1

2007-02-14 12:35:38 · 13 answers · asked by ♫♪♫ PINKY ♫♪♫ 5

2007-02-14 12:33:48 · 1 answers · asked by lena 1

2007-02-14 12:31:27 · 6 answers · asked by lena 1

2007-02-14 12:28:41 · 3 answers · asked by lena 1

2007-02-14 12:25:18 · 1 answers · asked by lena 1

a) a car exits a freeway and moves around a circular ramp to reach the street below
b)the moon orbits the earth
c)a father swings his child in a circle

2007-02-14 12:20:11 · 4 answers · asked by lena 1

If a skydiver has an acceleration of 9.81 m/s^2 (22 feet a second) and free-falls for 45 seconds why doesn't he break the sound barrier?
Is it wind resistance or what?

2007-02-14 12:19:01 · 5 answers · asked by Anonymous

a fish is dropped by a bird that rises at 0.5m/s, after 2s the velocity of the fish is -20.1m/s. how far below the bird is the fish after 2s?

2007-02-14 11:58:53 · 1 answers · asked by crazed1511 1

2007-02-14 11:50:06 · 5 answers · asked by Colton A 1

Space travelers from Earth have determined that on the Klingon planet 9-KMHF and object thrown upwards at the intial speed of 60 m/s returns to the surface after 3 sec. What is the gravitational acceleration on 9-kmhf??

please help thanks!1

2007-02-14 11:21:45 · 2 answers · asked by Anonymous

I need a flowchart of the endergy conversions while popping popcorn. Example: Chemical energy to physical energy to nuclear energy, etc.

2007-02-14 11:20:06 · 1 answers · asked by Alyssa L 1

2007-02-14 11:19:52 · 2 answers · asked by ras1969 1

A force of 100N is applied at tha point in a direction that is 60 to the left of y axis. The x and y components of the force vectors are?

I got Fx= - 50 Fy = 87

Am I right?? Please help thanks!!

2007-02-14 11:17:06 · 2 answers · asked by Anonymous

A 3.3 kg block starts (with its center-of-mass
vertical displacement at a height of 39 cm) on
a plane that has an inclination angle of 30degrees as
in figure.
Upon reaching the bottom, the block slides
along a horizontal surface. The coeffcient of
friction on both surfaces is meu= 0.3

How far does the block slide on the hori-
zontal surface before coming to rest? Answer
in units of m.

2007-02-14 10:41:28 · 1 answers · asked by kavita 1

2007-02-14 10:38:26 · 8 answers · asked by Anonymous

2007-02-14 10:33:43 · 7 answers · asked by kholio 1

2007-02-14 10:26:02 · 6 answers · asked by brandonjay 1