physics please HELP !

74,851 results, page 65
  1. physics

    If a race car completes a 2.8 mi oval track in 41 s, what is its average speed? Answer in units of mi/h
  2. Physics

    State the reason why a steel sphere resting on a horizontal surface is said to be in neutral equilibrium.
  3. physics

    Sound waves have which of these properties? A) Reflection.B) All of these.C) Refraction.D) Interference.E) Capable of producing beats.
  4. physics

    what is the net electrostatic force on the charge q3 -48ìc due to charges q1 (+78µC) and q2 (+50µC)
  5. Physics

    A boy sledding down a hill accelerates at 1.55 m/s2. If he started from rest, in what distance would he reach a speed of 6.90 m/s?
  6. physics

    a guy throws a ball up and catches it 3.5 seconds later. what is the max height and initial velocity. Please help!
  7. physics

    A 1.56kg seagull dives through the air and gains 4495 of energy.What is the birds speed?
  8. physics

    when two lenses of focal length +10cm and -5cm are placed in contact then find the net power ?
  9. physics

    Two equal point charges of +3.00 * 10^ -6 C are placed 0.200 m apart. What are the magnitude and direction of the force each charge exerts on the other?
  10. Physics

    What minimum speed does a 170 g. puck need to make it to the top of a 6.0 m. long, 27 frictionless ramp?
  11. physics please help

    Forces of 4.57 N and 4.74 N act at right angles on a reddish-green block of mass 5.76 kg. How much acceleration occurs?
  12. physics

    Calculate the watts of power expended when a force of 1.8 N moves a book 2.0 m in a time interval of 1.0 M/S
  13. physics

    A boy sledding down a hill accelerates at 1.20 m/s2. If he started from rest, in what distance would he reach a speed of 7.00 m/s?
  14. Physics

    Plane flying southwest at 155mi/hr. their is a wind from the west at 45.0mi/hr. what's the planes new velocity
  15. Physics

    You can run 8.0 m/s , 20% faster than your brother. How much head start should you give him in order to have a tie race over 90 m ?
  16. physics

    Frequency and period are related, in that they are which of the following?A) inverses of each other.B) None of these.C) both on the same wavelength.D) directly proportional to each other.E) two expressions for much the same thing.
  17. physics

    How fast (in ) must a centrifuge rotate if a particle 8.00 from the axis of rotation is to experience an acceleration of 117000 's?
  18. Physics

    At highway speeds, a particular automobile is capable of an acceleration of about 1.52 m/s2. At this rate, how long does it take to accelerate from 74.0 km/h to 104.0 km/h? (in s)
  19. Physics

    A car travels in a straight line for 4 h at a constant speed of 63 km/h. What is its acceleration? Answer in units of m/s^2?
  20. physics

    a glass plate 0.9m thick has a refractive index of long does it take a pulse of light to pass through it
  21. Physics

    A 1200 kg sports car accelerates from 0m/s to 27m/s in 10s. What is the average power of the engine?
  22. Physics

    C:\Users\100622325\Desktop\1.jpg Given the figure above, if a = 5.53 cm and b = 4.15 cm, what would be the force (both magnitude and direction) on the 5.0 nC charge?
  23. physics

    Discuss what happens when a man fires a pistol in front of a flight of stairs in a large hall.
  24. physics

    What is the frequency of the EM wave emitted most strongly by a glowing element on a stove with temperature 1,500 K
  25. physics

    find the force of a toy jeep if the mass is 50kg and is traveling at 4 m/s and the radius is 50 centimeter
  26. physics

    two equal vectors of magnitude 2A are inclime perpendicular to each other find the resultant and direction of vector.
  27. physics

    What is the magnitude of the average acceleration of a skier who, starting from rest, reaches a speed of 7.9 m/s when going down a slope for 7.4 s?
  28. physics

    Calculate the internal energy of 25.0 g of low-density oxygen gas (O2) at a temperature of 255 K.
  29. Physics

    A,B,C,D are four charges placed at each corner of a square, with A= -6.00 mC , B=6.00 mC, C=-6.00 mC and D=6.00 mC.ALso AB=BC=CD=DA=0.100 m.Determine the magnitude and direction of force on each charge.
  30. physics

    a metal spoon is placed in one of two indentical cups of hot coffee. Which cup will be cooler after a few minutes?
  31. physics

    compute the least acceleration with which a man of mass 75 kg can slide down a rope which can sustain a weight of 580 N
  32. physics

    A 8.2 kg object undergoes an acceleration of 2.5 m/s2. What is the magnitude of the resultant force acting on it? Answer in units of N
  33. Physics

    Find the orbital velocity of a satellite orbiting 1800km above sea level in meters per second?
  34. Physics

    A centrifuge has a rotational inertia of 6.0 10-3 kg · m2. How much energy must be supplied to bring it from rest to 420 rad/s?
  35. Integrated Physics and Chemistry

    What are a few of the positive things the Equal Rights Amendment would have done for women in America?
  36. Physics

    The formula is x = 1/2 at^2 and I have managed to fill in the variables as this. d = 1/2 9.81 m/s^2 1^2 I want to say that my answer is 4.905 but I'm unsure. Can someone check it?

    Calculate for Bohr's atomic model the speed of the orbiting electron in the n = 7 state. (Answer in m/s)
  38. Physics

    An object that starts from rest completes 7 revs in 3 seconds. What is angular accel. in rad/s2?
  39. physics-non calc

    a hammer was released from rest vi=0m/s taking 1.12 seconds to fall 1 meter. How do you solve that
  40. physics

    a body starting from rest attains a speed of 8 m/s in 2 seconds. find the acceleration of the car.
  41. physics

    how much time does it take for a student running t an average speed or 5.00m/s to cover a distance of 2.00km?
  42. physics

    What is the magnitude of the momentum of a car weighing 1,555 N when it is moving at a speed of 23 m/s? Express your answer in kg m/s.
  43. Physics

    What is the centripetal acceleration of an automobile driving at 40 km/h on a circular track of radius 20m? Help ASAP please!!!

    A Football is kicked 66.6 meters in 5.39 seconds. What was the initial velocity? Magnitude and Direction
  45. ap physics

    How fast would a 1200 kg car travel if it had the same linear momentum as a 1500 kg truck traveling at 90 km/h?
  46. physics

    A plane cruising at 251 m/s accelerates at25 m/s2 for 9 s.What is its final velocity?Answer in units of m/s
  47. physics

    an electric field of 640 v/m is desired between two metal plats 11.0 mm apart. how large a voltage should be applied?
  48. physics

    2)if a curved of radius 50m is banked at 30 degree will a car travelling at 60 km/hr along the curve will safe?
  49. Physics help please

    Calculate the allowed wavelengths for the emission of a photon initially in the n=3 state in a hydrogen atom

    A Carnot type engine has a reservoir of 1000 K with an efficiency of 50%. Find the temperature of the sink.
  51. physics

    a baseball is thrown horizontally at a velocity of 35 m/s from a height of 1.5 m. How long does it take to hit the ground? how far does it travel?
  52. Physics/Math

    The equation describing the motion of an object is y=0.8cos(4.2t+0.32). What is its period? I don't know how to figure this out?

    When the brake are applied to a moving car travelling 60km\hr it decelerate at uniform rate of 5m\s
  54. Physics

    How much work must be done to bring three electrons from a great distance apart to within 2.1×10−10 {\rm m} from one another (at the corners of an equilateral triangle)?
  55. physics

    a football is kicke with a velocity of 20 m/s at an angle of 40 degrees with the ground. Find the components. Key: 4 m/s = 1 cm
  56. Physics

    How much potential energy does Tim, with mass 60.0 kg, gain when he climbs a gymnasium rope a distance of 3.5m?
  57. Physics

    What is the de Broglie wavelength of an electron that strikes the back of the face of a TV screen at 1/9 the speed of light?
  58. physics

    Frequency and period are related, in that they are which of the following?A) inverses of each other.B) None of these.C) both on the same wavelength.D) directly proportional to each other.E) two expressions for much the same thing.
  59. Physics

    A 150 kg body is at rest and covers the constant force needed to impart a velocity of 8m/s to it in 5s.
  60. Physics

    a child twirls a yo-yo about in a horizontal circle. The yo-yo has a mass of 0.20 kg and is attached to a string 0.8 m long. what is the velocity of the yo-yo? thanks!
  61. Physics

    What push parallel to a 42 incline is required to just start a 340 N block sliding up the plane? us = 0.6
  62. physics

    a2kg hockey puck is sliding across the frictionless ice at 6m/ much force is required to keep it moving at 6m/s
  63. physics

    a projectile launched speed of 31.1m/s at angle 71.2 degrees above horizontal fill in table time 0 vx m/s 10.0m/s vy 29.4m/s ax? ay?
  64. physics

    A particle is projected with a speed of 39.2m/sec at an elevation of 30degrees.find its greatest height.
  65. physics

    Find the minimum kinetic energy needed for a 3.7×104-kg rocket to escape the Moon.
  66. science physics

    i don't get how to solve this please help me Two resistors, 47 Ù and 82 Ù, are connected in series across a 45 V battery. What is the current in the circuit?
  67. physics

    State the surface powers required to produce the following lenses with +6.25D front curves. a. -0.50 DS b. +0.50 DS c. +1.75 DS
  68. physics

    State the surface powers required to produce the following lenses with +6.25D front curves. a. -0.50 DS b. +0.50 DS c. +1.75 DS
  69. Physics

    If a car is going .197 meters per second, how long will it take to go 5 kilometers (assuming the ground is perfectly flat).
  70. physics

    What is the net force on a rock that weighs 500N if the weight of the water it displaces is 300N?
  71. Physics

    A 100-n boulder is sitting on a shelf 0.5 meters above the floor. What is the potential energy when its in its new location?
  72. Physics

    Suppose that you want to take a photograph of yourself as you look at your image in a flat mirror 1.6 away. For what distance should the camera lens be focused?
  73. Physics

    A child slides down a hill on a toboggan with an acceleration of 1.5 m/s squared. If she starts at rest, how far has she traveled in 1.0 s, 2.0 s, and 3.0 s?
  74. Physics

    Two objects are near a bar magnet. One is about 1 cm away, while the other is 6 cm away. Compare and contrast the magnetic force that affects each object. What do they want me to do?
  75. Physics

    What is the maximum total force exerted on a 71 kg astronaut by her seat during the launch of the Space Shuttle?
  76. college physics

    Is it possible for a frictional force to increase the mechanical energy of a system? If so, give examples.
  77. physics

    state the surface powers required to produce the following lenses with +6.25D front curves. a. -0.50 DS 6. +0.50 DS c. +1.75 DS
  78. physics

    You throw a ball downward from a window at a speed of 1.9 m/s. How fast will it be moving when it hits the sidewalk 2.2 m below?
  79. Physics

    What net external force is required to give a 30 kg suitcase an acceleration of 2.5 m/s2 to the right? Answer in units of N
  80. physics

    You throw a ball upward from a window at a speed of 2.9 m/s. How fast will it be moving when it hits the sidewalk 2.2 m below?
  81. Physics

    How much work is done by a girl weighing 450N while carrying a 2kg package up a 2m flight of stairs?
  82. physics

    A ball rolls off a 1.40 m high table with an initial horizontal speed of 0.600 m/s. How far will it land?
  83. physics

    What mass of ice at -14°C will be needed to cool 200cm³ of an orange drink(essentially water) from 25°C to 10°C?
  84. fristyear physics

    two girls a and b weighting 40 and 30 kg both of them pull 14m held by them.they will meet when covers a distance of?
  85. Physics

    A mass of gas has a volume of 380 cm3 at a pressure of 560 mm Hg and a temperature of 7C. What is its bolume at s.t.p.?
  86. physics

    What is the density of nitrogen gas (molecular mass = 28 u) at a pressure of 1.2 atmospheres and a temperature of 284 K?
  87. Physics

    Initial velocity is 21 m/s, the angle is 40 degrees, 20 meters away from the wall. How long is the ball in the air for?
  88. physics

    Where must an object be placed to have a magnification of 3.74 in front of a converging lens of focal length 14.1 cm?
  89. Physics

    A boy sliding down a frictionless plane inclined at an angles 35° with the horizontal. What is the acceleration of the book?
  90. Physics

    At the end of a race a runner decelerates from a velocity of 7.00 m/s at a rate of 0.500 m/s2. (a) How far does she travel in the next 14.0 s in meters?
  91. physics

    A rock is dropped from a height of 2 meters into a freshwater pond. What is the medium of the wave created?
  92. physics

    A particle is projected from ground in a vetical direction at t=0 sec. at t=0.8 s, it reaches h=14m .It will again come to the same height at ?
  93. physics

    two electric charges +10 microC and -20microC are located .35 m apart how much work is required to double the distance between them?
  94. physics

    Explain two different reasons why fibreglass is used to fill the space between the concrete block and the metal casing.
  95. physics

    2. A hockey player is skating in a straight line at 1.5 m/s. He then increases his speed to 7 m/s in 3 s. What is his average acceleration during this 3 s?
  96. physics

    a 60kg sprinter accelerates from rest at 2.5m/s east for 4s. what force is acting and what is his final speed?
  97. physics

    What force is necessary to keep a 2.00x10^3 car moving up a 15.0 degree incline at a constant velocity? (Mu=.200)
  98. physics

    a pendulum with a length of .600 m has a period of 1.55 s. what is acceleration due to gravity at the pendulums location
  99. physics

    A 30.0 kg block falls from a height of 30,4 m. assuming a closed system its speed just before hitting the ground is about?
  100. Physics

    What is the frictional force between the tires of a 2000 kg car and an asphalt road if the coefficient of friction is 1.2?