Physics - October 2006

A particle is shot upward from the ground with a velocity of v and at an angle of θ above the horizontal.
Using vectos notations, what are the expressions for v and a just before it hits the ground again??

2006-10-02 19:15:49 · 3 answers · asked by Anonymous

I worked out that 20mA = 20000A and 30 minutes = 1800s and I=Q/t

So that means Q=It = 20000 x 1800 = 360000000 C

My friends say i am wrong, can you please help me?

2006-10-02 18:53:06 · 4 answers · asked by Anonymous

Why do they use the same term for loudness of music and for space contained somehow? Is it because when I increase the volume of my speakers there's a bigger volume in which the sound can be heard or is it something else? more exotic, perhaps?

2006-10-02 18:26:16 · 5 answers · asked by Yankuta118 2

Please help me. And also give me some links/sites from where I can get related information.

2006-10-02 18:22:47 · 6 answers · asked by ssrirag2001 2

(a) Express the vector ~A= (Ax,Ay) = (−5 m,−2 m) using unit vectors ˆı and ˆ|.
Also express ~A in magnitude and direction form (|~A |, ), where the angle is measured
with respect to the positive x-axis, anticlockwise angles being positive.
(b) An acceleration vector of magnitude 9.81 m/s2 makes an angle of 75 with the positive
z-axis. Find the scalar components of the vector parallel to and perpendicular to the zaxis.
You now rotate the z-axis until the scalar acceleration component parallel to the
z-axis changes sign, becoming equal to the negative of its previous value. What now is the
angle between the vector and the z-axis?
(c) When vector ~C is subtracted from vector ~D , the resulting vector is equal to twice the
sum of the two vectors. Write this condition as a statement in vector algebra involving
~Cand ~D
. Show that this requires that ~D is a scalar multiple of ~C. Find the ratio of
the magnitudes of the two vectors, and the angle between them. Draw a diagram to show
their relationship.

2006-10-02 18:22:18 · 2 answers · asked by behshad c 1

At two points (1 and 2) in the motion of a particle, the instantaneous velocity
vectors have equal magnitudes of 20 m/s. At point 1, the velocity vector ~v1 points in the
positive x-direction. At point 2, the velocity vector ~v2 is at angle −45 to the positive
x-direction.
(a) Resolve ~v1 and ~v2 into rectangular scalar components. Do not forget the physical units.
(b) Take the difference of the two velocity vectors, ~v = ~v2 − ~v. Express this difference
in rectangular components.
(c) Divide the difference you found in part (b) by the time t = 6 s it took the particle
to travel between the two points. This gives ~v/t, the average acceleration ~aavg of the
particle over the interval between point 1 and 2 on the trajectory. Give the magnitude and
direction (angle with respect to the x-axis) of this average acceleration.

2006-10-02 18:21:35 · 1 answers · asked by behshad c 1

2006-10-02 17:58:10 · 4 answers · asked by juliecn01 1

A car accelerates from rest with a constant positive acceleration of ax = +2 m/ss,
then brakes with a constant negative acceleration ax = −4 m/ss, coming to a stop after a
total time interval of 30 s has elapsed. What are the distance traveled and the maximum
velocity reached by the car? (b) What are the car’s average velocity and average acceleration
for this interval?

2006-10-02 17:38:27 · 2 answers · asked by behshad c 1

how do you find the magnitude? for ex. if A is 3 m north and B is 3 m northeast, and the problem is you have to add A+B, what would be the magnitude? wouldn't it be 6 m?

2006-10-02 17:06:16 · 4 answers · asked by tingerpoo 2

If the cruise control is on and your car begins to hydroplane --when your tires lose contact with the pavement, your car will accelerate to a higher rate of speed and you take off like an airplane.

It doesn't sound right to me, but what do you think?

2006-10-02 16:55:15 · 9 answers · asked by vinny_the_hack 5

2006-10-02 16:43:25 · 22 answers · asked by mari the AWESOME 3

The temperatures cancel out and leave you with 1/time. So I'm assuming the dimensions of the constant would be some value per unit time. Unless its dimensionless?

Thanks!

2006-10-02 16:42:01 · 1 answers · asked by JoeSchmo5819 4

Bearing in mind, if I killed my father before I was born, firstly I would never be conceived nor would I be in the timeline, but if cant kill my father I would be conceived and would have had the opportunity to go back and kill him, but if I managed to kill him before I was conceived I would never be in the timeline? in the first place? Or would I?

2006-10-02 16:41:05 · 6 answers · asked by Anonymous

Don Beardon for real or scam artists.
what about compressed time in the 4th dimension?

2006-10-02 16:36:54 · 1 answers · asked by dogpatch USA 7

2006-10-02 16:34:02 · 2 answers · asked by Frontier's 2

At what 2 angles could the nozzle point in order that the water would land 2.0 m away

2006-10-02 16:24:58 · 3 answers · asked by hydrantman001 1

If light travels from fixed point A tofixed point B, A being in air and B in water, the route the ray chooses is completely different to that which it chooses if I, say, replace air with alcohol and water with glass. Both routes will not look like a straight line, for that matter. But still, this route will always be the most efficient one- Not too much time spent on the slow side and not too little time spent on the faster side- the ray always arriving at the quickest time it can to point B under the limitations. How is that explainable?

2006-10-02 16:23:41 · 2 answers · asked by Yankuta118 2

http://us.f13.yahoofs.com/bc/44436150me3e0859f/bc/My+Documents/Picture+1.png?bfwadIFBB1QyCb1K

I was hoping somewhat could explain to me how to do the above problem part A and B ( I know the answer to Part B is the last option)

2006-10-02 16:17:25 · 3 answers · asked by topgun553 1

2006-10-02 16:16:56 · 13 answers · asked by mrdranoel 1

is density a function of depth?

2006-10-02 16:04:38 · 5 answers · asked by ajflkajfsalkfsalkfna 3

A boy standing in a ditch throws a baseball upward toward his father. The ball leaves his hand at ground level, with an initial speed of 14.0 m/s, at an angle of theta = 61.0 degrees from the horizontal. The boy's father reaches up and catches the ball over his head, at a height of 2.0 m above the ground. The father catches the ball on its way down (as shown in the Figure). Calculate how long the ball is in the air. ( g = 9.81 m/s2)

Hint: You do not have to separate the upward and downward parts of this motion. You have enough information to find the horizontal and vertical components of initial velocity. You know the vertical displacment and acceleration. Be careful with signs.

2006-10-02 15:48:14 · 6 answers · asked by Jay 2

2006-10-02 15:48:08 · 1 answers · asked by Bubbly Brain 2

Iron Brass Copper
Mass (grams) 63.05g 48.10 63.40
Water (mL) 100mL 100mL 100mL
Initial water temp 21*C 21*C 21*C
Final water temp 66*C 72*C 63*C
Initial Metal temp 21*C 21*C 21*C
Final metal temp 62*C 68*C 58*C

change in temp metal 41*C 47*C 37*C
change in water temp 45*C 51*C 42*C

2006-10-02 15:45:30 · 1 answers · asked by Bubbly Brain 2

If I have y= -10m,Vy=0,and a = -9.8m/s^2. Need to solve for t or time?

2006-10-02 15:45:29 · 4 answers · asked by Anonymous

2006-10-02 15:40:11 · 2 answers · asked by rie_06 1

100mL water @ 21 degrees C, add an ice cube, then there is
125mL @ 7 degrees C after ice melts

2006-10-02 15:34:08 · 4 answers · asked by Bubbly Brain 2

i want to know the benefits of electricity in our economy,environment,in our health and our well being.

2006-10-02 15:27:43 · 2 answers · asked by kristie 1

Three astronauts, propelled by jet backpacks, push and guide a 120 kg asteroid toward a processing dock, exerting the forces with F1=32 N, with an angle of 30 degrees from the x-axis, F2=55 N along the x-axis, and F3=41 N with an angle of -60 degrees from the x-axis. WHat is the asteroid's acceleration, in vector notation and as a magnitude, and a direction relative to the positive direction of the x axis?

2006-10-02 15:05:33 · 1 answers · asked by afchica101 1

howw do you find the acceleration of an object if only given the speed?

2006-10-02 15:01:42 · 3 answers · asked by Anonymous

2006-10-02 14:56:49 · 12 answers · asked by a a 1