1. algebra

    a ball is thrown downward from the too of 110 ft bldg with an initial velocity of 14ft per second. the height of ball h after t seconds is given by the equation h = -16t^2-14t +110. how long after ball is thrown will it hit the ground
  2. Physics:upward acc of earth

    If the Earth's gravitational force causes a falling 93 kg student to accelerate downward at 9.8 m/s2, determine the upward acceleration of the Earth during the student's fall. Take the mass of the Earth to be Mearth = 5.98 x 1024 kg. Answer in units of
  3. science

    A particle leaves the origin with a speed of 2.4 times 106 m/s at 38 degrees to the positive x axis. It moves in a uniform electric field directed along positive y axis. Find Ey such that the particle will cross the x axis at x = 1.5 cm if the particle is
  4. Physics

    A spherical shell of radius R carries a uniform surface charge density (charge per unit area) σ. The center of the sphere is at the origin and the shell rotates with angular velocity ω (in rad/sec) around the z-axis (z=0 at the origin). Seen from
  5. Population Density - Geo

    predict the number of people that may live on planet earth in 100 years. how would i figure this out??
  6. physics

    How fast is a city on the earth's equator (such as Singapore) moving due to our planet's daily spin on its axis?
  7. science

    the motion of a planet on its axis is called a) rotation b)revolution c) shimmy d) wobble e) day the answer i picked was a
  8. science

    Define the main goals and strategies of green intelligence. Do you think market-based approaches could save the planet? Why or why not?
  9. Astronomy

    Why is most of the mass of the solary system contained in the Sun? Briefly describe the protoplanet theory of planet formation. Please help. thanks.
  10. MATH URGENT

    What distance would the skydiver fall during 7s of free fall ? Use the formula d= 4.9t^2, where in d is distance in meters and t is time in seconds. Pleeeeeeeeeese help me!!!!!!
  11. physics

    A 1.5-kg playground ball is moving with a velocity of 3.0 m/s directed 30 ° below thehorizontal just before it strikes a horizontal surface. The ball leaves this surface 0.50 slater with a velocity of 2.0 m/s directed 60 ° above the horizontal. What is
  12. Physics

    Two point charges +Q and -Q of mass m are placed on the ends of a massless rod of length L, which is fixed to a table by a pin through its center. If the apparatus is then subjected to a uniform electric field E parallel to the table and perpendicular to
  13. geometry

    to estimate the number of daises in a field students toss a ball into the field and mark a circular region with a radius of 15 feet from where the ball landed. the students then counted 35 daises in the circular region. if the entire field is approximately
  14. physics

    An electron (m0 = 9.11 10-31 kg) enters a uniform magnetic field B = 1.7 T, and moves perpendicular to the field lines with a speed v = 0.93c. What is the radius of curvature of its path?
  15. Physics

    An electron (m=9.11 * 10^-31) enters a uniform magnetic field B=1.8T and moves perpendicular to the field lines with a speed v=0.92c. what is the radius of curvature of its path?
  16. Physics

    A small plastic ball with a mass of 6.50x10^-3 kg and with a charge of +0.150x10^-6 C is suspended from an insulating thread and hangs between the plates of a capacitor. The ball is in equilibrium, whit the tread making an angle of 30 degrees with respect
  17. physics

    A small plastic ball with a mass of 6.50x10^-3 kg and with a charge of +0.150x10^-6 C is suspended from an insulating thread and hangs between the plates of a capacitor. The ball is in equilibrium, whit the tread making an angle of 30 degrees with respect
  18. Physics

    A small plastic ball with a mass of 6.50x10^-3 kg and with a charge of +0.150x10^-6 C is suspended from an insulating thread and hangs between the plates of a capacitor. The ball is in equilibrium, whit the tread making an angle of 30 degrees with respect
  19. Physics

    A small plastic ball with a mass of 6.50x10^-3 kg and with a charge of +0.150x10^-6 C is suspended from an insulating thread and hangs between the plates of a capacitor. The ball is in equilibrium, whit the tread making an angle of 30 degrees with respect
  20. math

    In a game of lawn bowls, the object is to bowl a biased ball so that it gets as close as possible to a smaller white ball called a jack. During a game, a player will sometimes bowl a ball quite quickly so that it travels in a straight line in order to
  21. physics

    A skier squats low and races down an 11◦ ski slope. During a 3 s interval, the skier accelerates at 2.7 m/s^2 . What is the horizontal component of the skier’s acceleration (perpendicular to the direction of free fall)? Answer in units of m/s^2.
  22. science-electromagnetism

    At a particular instant in the,in a region of space where E=0 and B=3i Wbm^-1 , a 2 kg particle of charge 1 C moves with a velocity of 2ims^-1.What is the particle's acceleration due to magnetic field?
  23. Physical Science

    If you were to expend 10 Joules of work to push a 1-coulomb charge against an electric field, what would be its voltage with respect to its voltage in its starting position? When released, what will be its kinetic energy if it flies past its starting
  24. Physics 112

    The inner and outer surfaces of a cell membrane carry a negative and a positive charge, respectively. Because of these charges, a potential difference of about 0.075 V exists across the membrane. The thickness of the cell membrane is 7.80 10-9 m. What is
  25. physics

    The physics of electric potential energy at one corner of a triangle. Two charges, q1 = +5.0 ìC and q2 = -2.0 ìC are 0.50 m apart. A third charge, q3 = +6.0 ìC is brought from infinity to a spot 0.50 m from both charges so that the three charges form an
  26. physics

    A charge of +24.3 µC is located at (4.40 m, 6.02 m) , and a charge of -13.1 µC is located at (-4.50 m, 6.75 m) . What charge must be located at (2.23 m, -3.01 m) if the electric potential is to be zero at the origin? ANyone have any advice? Find the
  27. physics

    1.In a cathode ray tube, electrons are accelerated from rest by a constant electric force of magnitude 6.56 x 10*-17 N during the first 1.87 cm of tube's length; then they move at essentially constant velocity another 45.0 cm before hitting the screen.
  28. College Physics

    A 12.0- A 12.0- A 12.0-V battery remains connected to a parallel plate capacitor with a plate area of 0.204m^2 and a plate separation of 3.14mm . What is the charge on the capacitor? Q = C How much energy is stored in the capacitor? Uc = J What is the
  29. Physics

    If a ball has a constant acceleration of 10m/s^2, how fast will the ball be rolling after 4 seconds? Would you multiply acceleration times time? So 10 x 4... or would you use the equation d=1/2gt^2?
  30. Physics

    Two charges +q and −q are separated by a distance d=50 cm. The electric field lines for this system form the the well-known pattern showed in the figure below. Consider two lines L1 and L2 lying on the same plane and leaving the positive charge at
  31. Electric fields and Coulomb's law

    Please, I need help with this question. An ion harvester is scouring deep space for isolated xenon (Xe+) ions. A xenon ion is singly ionized, and has a charge of +e. If the field meter reads 0.000000202 N/C, how far away is it from the ion?
  32. Physics (Electric fields and Coulomb's Law)

    I need help with this question please. An ion harvester is scouring deep space for isolated xenon (Xe+) ions. A xenon ion is singly ionized, and has a charge of +e. If the field meter reads 0.000000202 N/C, how far away is it from the ion? _________ m
  33. physics, help! urgent!

    A positive point charge q = +2.50 nC is located at x = 1.20 m and a negative charge of ƒ{2q = ƒ{5.00 nC is located at the origin. (a) Sketch the electric potential verses x for points on the x-axis in the range -1.50 m < x < 1.50 m. (b) Find a
  34. english

    At my son’s very first softball game his team did not do very well. No one seemed to be able to hit the ball or run the bases when they were up to bat. When they were in the field they would either run from the ball or be nowhere near it when they
  35. physics

    a small mass is suspended from a long thread so as to form a simple pendulum. The period . T of the oxillation depend on the thread and the acceleration. G of free fall at the place concerned so that. T=km^x,l^y,g^z.where k =2pie (1.) Find the value of
  36. tci college

    A brick undergoes a free fall from rest. Its initial height is 125 m above the ground. How long does it take to hit the ground? What is its maximum velocity before it makes impact? For ease of calculations, the magnitude of the acceleration of gravity is
  37. Physics

    If the gravitational force on you is 670N on the earth, how strong is the gravitational force on you on the surface of a neutron star that has the same mass as our sun and a diameter of 20.0km ? Take the mass of the sun to be ms = 1.99×1030kg , the
  38. physics

    The drawing shows the electric potential as a function of distance along the x axis. Determine the magnitude of the electric field in the following regions: A to B Bto C C to D C:\Users\Public\Pictures\mm\p19-56.gif
  39. physics

    The drawing shows the electric potential as a function of distance along the x axis. Determine the magnitude of the electric field in the following regions: A to B Bto C C to D C:\Users\Public\Pictures\mm\p19-56.gif
  40. physics

    The drawing shows the electric potential as a function of distance along the x axis. Determine the magnitude of the electric field in the following regions: A to B Bto C C to D C:\Users\Public\Pictures\mm\p19-56.gif
  41. Physics

    Suppose that the electric field of an electromagnetic wave decreases in magnitude. Does the magnetic field increase, decrease, or remain the same? Account for your answer.
  42. Physics

    Two point charges of 2.0 nC and 6.0 nC are both located 1.0 m away from a third charge of 3.0 nC ("n" is the metric prefix "nano" and means 10^-9) as shown. What is the electric force (magnitude and direction) on the 3.0 nC charge? 3.0 nC O---------O 6.0
  43. Physics

    A 45-t electric train accelerates uniformly from a station with the train’s motion depicted in the graph in Figure 2.(Recall that 1 t = 1.0 × 103 kg.)Determine the net force acting on the train during the uniform acceleration portion of the motion.
  44. physics

    help please?? A bocce ball with a diameter of 6.00 cm rolls without slipping on a level lawn. It has an initial angular speed of 2.35 rad/s and comes to rest after 2.50 m. Assuming constant deceleration, determine (a) the magnitude of its angular
  45. physics

    A quarterback throws the football to a stationary receiver who is 22.7m down the field. the football is thrown at an initial angle of 39 degrees to the ground. The acceleration of gravity is 9.81m/s^2. a) at what initial speed must the quarterback throw
  46. Math

    A ball is thrown downward from the top of a 100-foot building with an initial velocity of 14 feet per second. The height of the ball h after t seconds is given by the equation h=-16t^2-14t+100. How long after the ball is thrown will it strike the ground?
  47. physics

    A ball is thrown directly downward, with an initial speed of 11m/s, from a height of 56m. After what time interval does the ball strike the ground?
  48. physics

    examples of: 1) acceleration against the direction of motion 2) acceleration in direction of motion 3)acceleration is uniform 4)acceleration is non-uniform
  49. physics

    A 15.0 m, 500 N uniform ladder rests against a frictionless wall, making an angle of 60 0 with the horizontal, as shown in Figure Q3(a). Draw the free body diagram and calculate the normal force FN exerted by the wall, horizontal FBI and vertical Fv forces
  50. physics

    Two small pith balls, each of mass m = 11.2 g, are suspended from the ceiling of the physics lab by 1.7 m long fine strings and are not moving. If the angle which each string makes with the vertical is è = 30.4°, and the charges on the two balls are
  51. Physics Please HELP!!!!!!!!!

    Two small pith balls, each of mass m = 11.2 g, are suspended from the ceiling of the physics lab by 1.7 m long fine strings and are not moving. If the angle which each string makes with the vertical is è = 30.4°, and the charges on the two balls are
  52. physics

    Two small pith balls, each of mass m = 11.2 g, are suspended from the ceiling of the physics lab by 1.7 m long fine strings and are not moving. If the angle which each string makes with the vertical is è = 30.4°, and the charges on the two balls are
  53. chem

    plz help If you carefully place a steel razor blade flat on the surface of water, the razor blade can be made to float. Explain this result, given that the density of steel is much greater than that of water. I'm not really sure what the answer is. I think
  54. AP physics

    A NFL punter kicks a ball and lands 52 m away and is in the air for 4.8s. Assume that the ball lands at the same level that is is kicked. a. determine the initial velocity of the punt (magnitude and direction) b. determine the maximum height of he punt c.
  55. Chem

    Specify the number of unpaired electrons for each of the species shown below. CuCl2- (linear) Ni(NH36) 2+ NiCl4 2- (tetrahedral) CoF6 3- (weak field) Co(en)3 3+ (strong field) (en = "ethylene diamine") Would it be: 1 2 2 3 3 ??
  56. physics

    Assuming the Earth's magnetic field averages about 0.50×10−4 T near Earth's surface, estimate the total energy stored in this field in the first 15km above Earth's surface. The radius of Earth is 6380 km.
  57. physics

    A car starts from rest and travels for 5.0 seconds with a uniform acceleration of +1.5 m/s^2. The driver then applies the brakes, causing a uniform acceleration of -2.0 m/s^2. If the brakes are applied for 3.0 seconds, how fast is the car going at the end
  58. physics

    A charged capacitor (AB) carries on its plate A a charge Q=-1.2mC a) What is the charge carried by plate B. b) Is the voltage U (AB)=V (A)-V (B) positive or negative. c) The plates A and B are connected to the terminals of a resistance R: the capacitor
  59. Physics

    A flat thin non-conducting ring has an inner radius R1 and an outer radius R2 . The disk is uniformly charged with charge per unit area σ(>0) . (a) What is the electric field at the center, P , of the ring? Express your answer in terms of the
  60. Physics

    A synchronous satellite, which always remains above the same point on a planet's equator, is put in orbit around Neptune so that scientists can study a surface feature. Neptune rotates once every 16.1 h. Use the data of Table 13.2 to find the altitude of
  61. physics

    A spacecraft is in orbit close to the moon's surface. The centripetal acceleration is 1.6 m/s^2. If the radius of the moon is about 1.7 x 10^6 m, determine: a)the orbital speed b)the period of the orbit
  62. physics

    When you lift a bowling ball with a force of 60.7 N, the ball accelerates upward with an acceleration a. If you lift with a force of 69.3 N, the ball's acceleration is 1.99a. Calculate the weight of the bowling ball.
  63. physics

    When you lift a bowling ball with a force of 69.3 N, the ball accelerates upward with an acceleration a. If you lift with a force of 77.2 N, the ball's acceleration is 2.00a. Calculate the weight of the bowling ball. For this should I add both force
  64. Physics

    A ball on the end of a string is whirled around in a horizontal circle of radius 0.486 m. The plane of the circle is 1.83 m above the ground. The string breaks and the ball lands 2.39 m away from the point on the ground directly beneath the ball’s
  65. Physics

    A ball on the end of a string is whirled around in a horizontal circle of radius 0.486 m. The plane of the circle is 1.83 m above the ground. The string breaks and the ball lands 2.39 m away from the point on the ground directly beneath the ball’s
  66. Physics

    I don't know if my other post went through or not, so I'm reposting it here. The first question I didn't know the answer to and the second one was worded in a way that I couldn't understand. 1. With respect to an electric and a magnetic field, how does the
  67. English

    No charge does it mean free example: Art Gallery of Queensland - No charge please help
  68. physics

    Indicate true or false in each of the following statements: 1. A static magnetic field can do work on a current carrying wire when the current in the wire is perpendicular to the field. 2. The time required for a charged particle to complete one cycle of a
  69. Physics

    A bowling ball rolls without slipping up a ramp that slopes upward at an angle (beta) to the horizontal. Treat the ball as a uniform, solid sphere, ignoring the finger holes. What is the acceleration of the center of mass of the ball? Express your answer
  70. Science(Stuff to do like with magnets!)

    1. A positively charged test object is moving toward the positive source charge in an electric field. What happens next??? A. its potential energy decreases. B. Its potential energy increases. C. Its potential energy stays the same. D. Its potential energy
  71. Physics

    A projectile is fired at 65.0° above the horizontal. Its initial speed is equal to 37.5 m/s. Assume that the free-fall acceleration is constant throughout and that the effects of the air can be ignored.At what time after being fired does the projectile
  72. Physics

    A ball swings in a vertical circle at the end of a rope 1.50 m long. When the ball is 35.9° past the lowest point on its way up, its total acceleration is (-22.5 i + 20.2 j)m/s^2. Find radial acceleration?
  73. Physics

    Horizontal electric power lines supported by vertical poles can carry large currents. Assume that Earth’s magnetic field runs parallel to the surface of the ground from south to north with a magnitude of 0.50××10^-4 Tesla and that the supporting poles
  74. Physics

    A 0.7 um-diameter droplet of oil, having a charge of +e, is suspended in midair between two horizontal plates of a parallel-plate capacitor. The upward electric force on the droplet is exactly balanced by the downward force of gravity. The oil has a
  75. math

    an astronomer estimated that a canyon on another planet was 2.5x10^3 kilometers long which is equivalent 25,000km 2,500km 0.025km 0.0025km please help
  76. Math(Dynamics)

    To find the time taken by a planet to describe a given arc of its elliptic orbit starting from the nearer and of the major axis.
  77. physics

    an object weighs 10N on earth .what is the objects weight on a planet one tenth the earths mass and one half its radius?
  78. science

    Is venus the 1st, 2nd, 3rd, 4th, 5th, 6th, 7th, 8th or 9th smallest planet?
  79. Math

    Let d(t) be the shortest distance between Earth and the nearest other planet as a function of time t (where t is in years and t = 0 is noon on January 1, 1000 A.D., say). Is d continuous? Why or why not?
  80. physics

    A 25000 kg rock is located at a distance of 7.6 x 108 m away from a small planet of mass 7.8 x 1023 kg. What is the mutual force of attraction between these two
  81. English

    The contestants in the quiz show sat wth we,us audience members. I think us because it is an object? For we, us scientist, the discovery of a new planet would be exciting. I think us?
  82. Science

    Three identical 10 micro farad capacitors are connected in series across a 100V DC supply...calculate the total charge
  83. Physics

    A ball on the end of a string is whirled around in a horizontal circle of radius 0.33 m. The plane of the circle is 1.21 m above the ground. The string breaks and the ball lands 2.22 m away from the point on the ground directly beneath the ball’s
  84. physics

    A ball on the end of a string is whirled around in a horizontal circle of radius 0.33 m. The plane of the circle is 1.26 m above the ground. The string breaks and the ball lands 2.4 m away from the point on the ground directly beneath the ball’s location
  85. physics

    A laboratory centrifuge on earth makes n rpm (rev/min) and produces an acceleration of 3.30 g at its outer end. This centrifuge is now used in a space capsule on the planet Mercury, where g mercury is 0.378 what it is on earth. How many rpm (in terms of n)
  86. physics

    a square with side length 2.0 cm has a charge of -1.0x10^-6C at every corner. What is the magnitude and direction of the electric force on each charge? What is the force on a fifth charge placed in the centre of this square? Does the sign of the fifth
  87. Physics

    A small plastic ball with a mass of 6.80 10-3 kg and with a charge of +0.161 µC is suspended from an insulating thread and hangs between the plates of a capacitor (see the drawing). The ball is in equilibrium, with the thread making an angle of 30.0°
  88. physics

    A small plastic ball with a mass of 7.00 10-3 kg and with a charge of +0.162 µC is suspended from an insulating thread and hangs between the plates of a capacitor (see the drawing). The ball is in equilibrium, with the thread making an angle of 30.0°
  89. coll physics II

    A small plastic ball of mass 6.10 10^3 kg and charge +0.150 µC is suspended from an insulating thread and hangs between the plates of a capacitor. The ball is in equilibrium, with the thread making an angle of 30.0° with respect to the vertical. The area
  90. physics

    A small plastic ball with a mass of 7.00 10-3 kg and with a charge of +0.162 µC is suspended from an insulating thread and hangs between the plates of a capacitor (see the drawing). The ball is in equilibrium, with the thread making an angle of 30.0°
  91. Physics

    A small plastic ball with a mass of 6.80 10-3 kg and with a charge of +0.161 µC is suspended from an insulating thread and hangs between the plates of a capacitor (see the drawing). The ball is in equilibrium, with the thread making an angle of 30.0°
  92. phy.

    Larry weighs 300 N at the surface of the earth. what is the weight of the earth in the gravitational field of Larry? -force= GMm/d^2 would i set it up like force= (9.8m/s^2)(300 N)? an astronaut lands on a planet that has twice the mass as earth and twice
  93. physics

    A ball is thrown vertically upwards, from ground level, with an initial speed vo. Assume that air resistance is negligible so that the acceleration of the ball is due solely to gravity. a) Derive an algebraic formula for the time t that it takes for the
  94. Physics

    The drawing shows a large cube (mass = 25 kg) being accelerated across a horizontal frictionless surface by a horizontal force . A small cube (mass = 4.0 kg) is in contact with the front surface of the large cube and will slide downward unless is
  95. Physics

    The drawing shows a large cube (mass = 48 kg) being accelerated across a horizontal frictionless surface by a horizontal force . A small cube (mass = 2.1 kg) is in contact with the front surface of the large cube and will slide downward unless is
  96. Physics - Electric Potential

    A charge of - 0.15 C is moved from a position where the electric potential is 13 V to a position where the electric potential is 60 V. What is the change in potential energy of the charge associated with this change in position?
  97. statistics

    a binomial distribution will be approximately correct as a model for one of these two sports settings and for the other. explain why by briefly discussing both settings. a)a national football league kicker has made 80% of his field goal attempts in the
  98. Advanced physical science

    An astronaut drops a golf ball to the surface of the moon from a height of 1.5m. The golf ball has a velocity of 2.24 m/s right before it lands on the moon (assume this height to be zero). What is acceleration due to gravity on the moon?
  99. Science

    1)Newton's laws of motion are concerned with relationships among a) force, mass and motion b) Displacement, mass and acceleration c) Velocity, fore and acceleration d) mass, acceleration and velocity I feel that thay deal with force, mass and motion which
  100. Physics

    A loaded elevator with very worn cables has a total mass of 3000 kg, and the cables can withstand a maximum total tension of 40,000 N. (a) What is the maximum upward acceleration for the elevator if the cables are not to break? (b) What must the tension be