Physics - October 2007

2007-10-10 07:13:30 · 4 answers · asked by chris 1

constant acceleration, HOW WOULD ONE GO ABOUT SOLVING THIS?

2007-10-10 07:07:37 · 4 answers · asked by a s 1

2007-10-10 06:53:22 · 3 answers · asked by gnasherr 2

find the body's speed & acceleration of S= 8t - t^2 @ the endpoints of the interval 0<_ t <_ 5

2007-10-10 06:37:38 · 2 answers · asked by jewel7962002 1

Why is extremely high pressure required to cause atomic nuclei to crash into one another in stars ??

2007-10-10 06:35:03 · 4 answers · asked by Ben M 1

2007-10-10 06:25:24 · 2 answers · asked by Anonymous

An automobile traveling at a speed of 30 m/s applies its brakes and comes to a stop in 4.9 s. If the automobile has a mass of 0.8 " × 10^3 kg, what is the average horizontal force exerted on it during braking? Assume the road is level.

2007-10-10 05:20:05 · 5 answers · asked by Anonymous

A piano whose mass is 170 kg is being lifted at a steady speed from ground level straight up to an apartment 10.6m above the ground. The crane that is doing the lifting produces a steady power of 560W. How much time does it take to lift the piano?

2007-10-10 05:17:37 · 2 answers · asked by Anonymous

2007-10-10 04:58:14 · 2 answers · asked by davidwgalbraith 1

With no load resistor across the output terminals of the amplifier, and Vin = 0.25 V, the output voltage, Vout = 5 V. With a resistor of 50 Ω across the output terminals, Vout = 2 V. What is the output resistance of the op-amp?

Thanks in advance!

2007-10-10 04:49:07 · 1 answers · asked by squishy 1

In theory what would the difference be between linear and perpendicular time? How would it affect humans if we lived in that time?

2007-10-10 04:21:11 · 4 answers · asked by Elizabeth M 2

I am confused as to what to do on this problem. Could someone help me? Thanks!

A 67.8 g ball is dropped from a height of 67.3 cm above a sprin of negligible mass. The ball compresses the spring to a maximum displacement of 4.76386 cm. The acceleration of gravity is 9.8 m/s^2. Calculate the spring force constant k. Answer in units of N/m.

2007-10-10 04:09:41 · 3 answers · asked by sg88 1

An Olympic basketball player shoots towards a basket that is 5.86 m horizontally from her and 3.05 m above the floor. The ball leaves her hand 1.57 m above the floor at an angle of 43.0o above the horizontal.
What initial speed should she give the ball so that it reaches the basket and hopefully scores?

2007-10-10 03:36:49 · 3 answers · asked by Anonymous

(via a rope) with a force of magnitude Fr = 45 N. As the block slides through distance d = 0.25 m along the ramp, its kinetic energy increases by 90 J. How much greater would its kinetic energy have been if the rope had not been attached to the block?

2007-10-10 03:19:53 · 2 answers · asked by tosinjesu 1

2007-10-10 03:06:24 · 2 answers · asked by Anonymous

When a parachute opens, the air exerts a large drag force on it. This upward force is initially greater than the weight of the sky diver and, thus, slows him down. Suppose the weight of the sky diver is 956 N and the drag force has a magnitude of 1025 N. The mass of the sky diver is 97.6 kg. What are the magnitude and direction of his acceleration?

2007-10-10 02:59:46 · 1 answers · asked by jukeb0xqirl 2

2007-10-10 02:27:40 · 9 answers · asked by Asker 6

A spring does not have an extension proportional to load at the very beginning because there is a certain amount of force you need to apply to a spring before there is any extension. What is this point called and what is a better explanation for it?

2007-10-10 01:44:36 · 1 answers · asked by Mbolt 2

Two men sitting on wheeled supermarket trolleys

In scenerio Mr A pulls on the rope, other end is tied to Mr B trolley. He isnt holding it.

i) who will move towards who? Will one move and other not if so who otherwise will both move towards each other?
ii) have to choose between the following:
the rope exerrts a force on B not on a
the rope exerts a force on A not on B
THE rope exerts force on both and forces same size
the rope exerts force on both, force on B is bigger
the rope exerts force on both, force on A is bigger

2007-10-10 01:24:53 · 2 answers · asked by Anonymous

If you step off a ledge, you accelerate noticeably toward the earth because of the gravitational interaction between you and the earth. Does the earth accelerate toward you as well? Explain.

2007-10-10 00:08:38 · 2 answers · asked by Anonymous

the second question would be: who was the person and in what industry?

2007-10-09 20:07:25 · 3 answers · asked by c_r_a_z_y_f_r_o_g008 2

The current through a 3.0mH inductor is being built up from zero by a 1.5V battery. the equivalent series resistance of the circuit is 6.0 ohms.

a) Calculate the inductive time constant?
____________s

b) Calculate the current 2.3ms after the swith is closed.

___________mA


when 250 mA flows through a 3.0 mH inductor switches are thrown so that the current begins to decay with an equivalent series resistance of 6.0 ohms and no battery. Calculate the current 2.3 ms after the switch is closed

_________________mA

2007-10-09 19:18:20 · 2 answers · asked by Foxx 1

2007-10-09 19:17:39 · 6 answers · asked by ndungupatoh 1

The Grand Coulee Dam is 1270 m long and 170 m high. The electrical power output from generators at its base is approximately 1920 MW.
How many cubic meters of water must flow from the top of the dam per second to produce this amount of power if 93.0 \% of the work done on the water by gravity is converted to electrical energy? (Each cubic meter of water has a mass of 1000 {\rm kg}.)

2007-10-09 19:09:54 · 3 answers · asked by Madiyar T 1

2007-10-09 19:00:14 · 3 answers · asked by Anonymous

A tire placed on a balancing machine in a service station starts from rest and turns through 4.7 revolutions in 1.1 s before reaching its final angular speed. Calculate its angular acceleration.
____rad/s2

2007-10-09 18:58:17 · 1 answers · asked by burkehud 2

Are these anything like polar coordinates or cylindrical coordinates?

2007-10-09 18:56:32 · 2 answers · asked by PT109 1

reference frame. a) Where does the ball land? What is your answer if the car B)accelerates c)Deccelerates d)rounds a curve e) moves with constant velocity but is open to air?

2007-10-09 18:44:28 · 4 answers · asked by Anonymous

Do the energy forces on the outside of galaxies have the same amount of energy forces into the closer regions, or center of the galaxy. ie. Will something of the same size and mass carry the same force and gravitational pull in different areas of a galaxy?

2007-10-09 18:32:24 · 4 answers · asked by velocityfirst 2

A parachutist relies on air resistance (mainly on her parachute) to decrease her downward velocity. She and her parachute have a mass of 57.5 kg and air resistance exerts a total upward force of 660 N on her and her parachute.

What is the combined weight of the parachutist and parachute in newtons?
Calculate the net force on the parachutist.
What is the magnitude of the acceleration of the parachutist?

2007-10-09 18:13:31 · 1 answers · asked by Anonymous