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  Can a bird fly in zero gravity?

  Posted by deonokin on Dec 7, 2009 at 07:37 PM

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  A ball with mass m = 0.2 kg falls  free on a horizontal plane, having at time of collision, the velocity v = 16m / s.

  Posted by xuediot on Dec 7, 2009 at 05:52 AM

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  A girl is pushing on the handle of a lawnmower with a force of 100 N by making an angle of 30 degree with the ground. (a) Find the vertical .....

  Posted by lucky092569 on Dec 4, 2009 at 05:00 AM

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  The height, h, in meters above the ground, of a projectile at any time, t, in seconds, after launch is defined by the function h=-4t^2+48t+3...

  Posted by dreanna on Dec 3, 2009 at 09:24 AM

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  What is inertia?

  Posted by nerd1772 on Dec 2, 2009 at 05:07 PM

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  Bird flies w/ speed of 12.2 over water, drops fish. a=gravity at 9.81. The alt. of bird=5.3. Air resistance=none. What is the bird speed at impact?

  Posted by madisonliz on Nov 29, 2009 at 06:50 PM

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  Why can the mass of an electron can be ignored in a nuclear reaction involving protons and neutrons?

  Posted by buffy-the-vampire-slayer on Nov 24, 2009 at 05:31 PM

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  Xray pulses from Cygnus X1, a celestial xray source, have been recorded during high-altitude rocket flights.

  Posted by won on Nov 24, 2009 at 05:19 AM

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  Find magnitude of gravitational force a61.8kg person experience while standing on surface of Earth with mass of 5.98x10^24kg and a radius of6.37x10^m.

  Posted by lala2pretty on Nov 24, 2009 at 05:11 AM

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  If the period of asteroids orbit is2.011221777 in units of yr,then whats the orbital velocity of asteroid?Assume there 365 days in 1 yr.Answer in m/s

  Posted by juniormax on Nov 24, 2009 at 05:04 AM

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  Can an object have kinetic energy and potential energy at the same time?

  Posted by eightgraderhelpme on Nov 23, 2009 at 07:29 PM

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  A 10kg chandelier lamp is hanged by a 2m rope from a 6 m height ceiling. Calculate the potential energy of the lamp from the ceiling.

  Posted by yan2424 on Nov 23, 2009 at 12:55 PM

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  A satellite moves in a circular orbit around the Earth at a speed of 5.1 km/s. Determine the satellite's altitude above the surface of the Earth.

  Posted by jharry23 on Nov 23, 2009 at 05:05 AM

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  Two balls, each with a mass of 0.813 kg, exert a gravitational force of 8.38 x 10^-11 N on each other.

  Posted by jayy000 on Nov 23, 2009 at 04:57 AM

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  How does the force of gravity between two bodies change when the distance between them doubles?

  Posted by kela000 on Nov 23, 2009 at 04:51 AM

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  Two 3.4g bullets are fired with speeds of 42.9m/s and 77.4m/s, respectively a) if the kinetic energy of the first bullet is 3.128697 in units of J.

  Posted by lala2pretty on Nov 22, 2009 at 11:49 AM

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  A 1.98 kg ball is attached to a ceiling by a 2.1 m long string. The height of the room is 5.95 m. The acceleration of gravity is 9.8 m/s2.

  Posted by juniormax on Nov 20, 2009 at 11:39 AM

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  A 46kg pole vaulter running at 11m/s vaults over the bar. Her speed when she is above the bar is 1m/s. The acceleration of gravity is 9.8m/s^2.  

  Posted by lala2pretty on Nov 20, 2009 at 11:37 AM

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  By what factor does the kinetic energy of a car change when its speed is tripled?

  Posted by hrrjack on Nov 20, 2009 at 07:14 AM

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  If the velocity of an object quadruples while falling, by what factor would the kinetic energy and momentum increase, respectively?

  Posted by lala25 on Nov 20, 2009 at 07:12 AM

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  Consider the collision of two identical parti-cles, with m1 = m2 = 10 g.The initial velocity of particle 1 is v1 and

  Posted by papertissue on Nov 19, 2009 at 10:32 PM

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  A 70 kg cart is pushed for 50 m with a constant velocity upon a 45º frictionless incline. What is the work done on the cart?

  Posted by seeing-purple on Nov 18, 2009 at 06:45 AM

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  Calculate the speed of an 8.4 x 10 to the 4th power kg airliner with a kinetic energy of 1.0 x 10 to the 9th power J. Answer in units of m/s.

  Posted by jharry23 on Nov 18, 2009 at 05:34 AM

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  A motorist makes a journey of 240 km from Singapore to Malacca to visit his in-laws at an average speed of x km/hr. Write down an expression for ...

  Posted by lucky092569 on Nov 17, 2009 at 07:48 PM

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  Tim, with mass 64.3 kg, climbs a gymnasium rope a distance of 3 m. The acceleration of gravity is 9.8 m/s to the second power.

  Posted by jayjay00 on Nov 17, 2009 at 05:54 AM

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  A racing car has a mass of 1610 kg. The acceleration of gravity is 9.8 m/s to the second power.

  Posted by shawn123 on Nov 17, 2009 at 05:50 AM

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  Calculate the speed of an 8.4 x 10 to the fourth power kg airliner with a kinetic energy of 1.0 x 10 to the tenth power J.

  Posted by kela000 on Nov 17, 2009 at 05:47 AM

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  A commonly used unit is the kilowatt hour. The physical quantity measured in kilowatt hours is

  Posted by lala25 on Nov 17, 2009 at 05:44 AM

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  A block of mass 3.82 kg is pushed 2.91 m along a frictionless horizontal table by a constant 16 N force directed 24 degrees below the horizontal.

  Posted by hrrjack on Nov 17, 2009 at 05:41 AM

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  754 N diver drops from a board 9.00 m above the water's surface. The acceleration of gravity is 9.81 m/s^2.

  Posted by harris123 on Nov 17, 2009 at 05:31 AM

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  Two bullets have masses of 2.6 g and 5.7 g, respectively. Each is fired with a speed of 39.0 m/s.

  Posted by jharry23 on Nov 17, 2009 at 05:26 AM

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  A roller coaster cart of mass m=351 kg starts stationary at point A, where h1= 29.2 m and a while later is at B, where h2= 10.1 m.

  Posted by juniormax on Nov 17, 2009 at 04:54 AM

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  In a gaseous mixture of massive molecules and light molecules with the same average KE, which have the greater speed?

  Posted by hrrjack on Nov 16, 2009 at 05:11 AM

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  A 2.0 kg block is pushed 3.0 m at a constant velocity up a vertical wall by a constant force applied at an angle of 25.0◦ with the horizontal.

  Posted by thekonstant on Nov 15, 2009 at 12:43 PM

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  A shopper in a supermarket pushes a cart with a force of 38 N directed at an angle of 25 ◦ downward from the horizontal.

  Posted by stepiigza on Nov 13, 2009 at 10:26 PM

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  How Photoelectric effect is a proof of energy quantification?

  Posted by fairydrink on Nov 13, 2009 at 02:45 AM

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  A source with electric voltage  E and r debits  the same power on the R1 =4ohms and  R2 = 9 ohms.

  Posted by sixpenpencil on Nov 13, 2009 at 01:00 AM

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  It can change the speed of an electron under the action of a constant magnetic field in time?

  Posted by realcomplexnr on Nov 13, 2009 at 12:49 AM

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  A bulb of 24W and 12V is fed to 72 V. What is the resistance in series, R series, for the normal functioning of the bulb?

  Posted by nena1993 on Nov 13, 2009 at 12:45 AM

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  What minimum power must the motor deliver to lift the fully loaded elevator at a constant speed 3.25 m/s? Answer in units of kW.

  Posted by lala25 on Nov 9, 2009 at 08:42 AM

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  A block of mass 3.54kg is pushed 1.19m along a frictionless horizontal table by a constant 16N force directed 27 degrees below the horizontal

  Posted by hrrjack on Nov 9, 2009 at 07:25 AM

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  Find the work she does on the flight bag. Answer in units of J. Find the work done by the force of friction on the flight bag. Answer in units of J.

  Posted by lala2pretty on Nov 9, 2009 at 07:16 AM

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  A ball rolls with an acceleration of -0.5m/s squared. If it stops after 12s, what was its initial speed?

  Posted by m021761m on Nov 8, 2009 at 05:13 PM

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  Find the work done by the force of friction on the flight bag.

  Posted by shawn123 on Nov 5, 2009 at 05:42 AM

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  Find the work she does on the flight bag. Answer in units of J.

  Posted by jayjay00 on Nov 5, 2009 at 05:41 AM

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  What is Fn of the incline on the block? Answer in units of N.

  Posted by harris123 on Nov 5, 2009 at 05:17 AM

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  Why do rough surfaces increase friction?

  Posted by dcutesarah on Nov 5, 2009 at 03:03 AM

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  Explain how a screw driver could be used as a lever and as a wheel and axle device.

  Posted by rebecca9625 on Nov 4, 2009 at 02:31 PM

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  A catcher "gives" with a baseball when catching it.

  Posted by jharry23 on Nov 4, 2009 at 05:58 AM

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  A tugboat pulls a ship with a constant net horizontal force of 6.92 x 10 to the third power N and causes the ship to move through a harbor.

  Posted by shawn123 on Nov 4, 2009 at 05:41 AM