physics please HELP !

74,851 results, page 95
  1. Physics

    A flywheel has a moment of inertia of 2.6 kg·m2. What is the average power needed to spin it up from rest to an angular velocity of 100 rad/s in 30 seconds?
  2. Physics

    Find the energy necessary to put 5kg , initially at rest on Earth's surface, into geosynchronous orbit. do i use the formula U=-GMm/r I get 290 MJ?
  3. Physics

    Describe the steps necessary to convert a parabolic decreasing curve to a liner graph. That's is one with the relationship between two variables give a straight line.
  4. physics

    What is the critical angle of light traveling from benzene (n=1.501) into air? Choose one answer. a. 40.05o b. 48.22o c. 41.78o d. 62.63o
  5. physics

    A group of students observes that a wooden block (m = 0.40 kg) on the end of a string with a radius of 0.7 meters makes 5 rotations in 20.7 seconds when twirled.
  6. physics

    A ball is thrown directly downward with an initial speed of 8.95 m/s, from a height of 29.0 m. After what time interval does it strike the ground? answer in (in seconds)
  7. Physics

    By what amount will a 178 m long concrete slab on the Mackinac Bridge contract when going from +39C to -35C? The linear expansion coefficient is 10-5 per C.
  8. Physics

    A uniform beam of mass 2kg and length 4cm is rotated about an axis 8cm from one end.Determine it's moment of inertia
  9. physics

    3 equal charges each of of 2*10-6 C are fixed at three corners of an equilateral triangle ofsides 5 cm.find the column force experienced by one of the charge due to the other two
  10. physics

    If 4.5 kg object is sitting at rest on a 30 degree incline that has a coefficient of static friction of .19, what is the net force down the plane? Does it start sliding?
  11. physics

    a converging lens has a focal length of 15cm. Find two positions where a real object can produce images four times its size.
  12. Integrated Physics and Chemistry

    Some refrigerants used in air conditioners have been associated with... A)smog B)destruction of the ozone layer C)thermal pollution D)power failures
  13. Physics/English/Nautical Mile

    In my previous posts about the NM I think part of my problem is I do not understand the meaning of the word "SUBTENDED". Explanation please. Mike
  14. physics

    A ball is thrown vertically upward with a speed of 19.0 m/s. (a) How high does it rise? (in meters) (b) How long does it take to reach its highest point? (in seconds)
  15. Physics

    A group of students observes that a wooden block (m = 0.40 kg) on the end of a string with a radius of 0.7 meters makes 9 rotations in 20.7 seconds when twirled.
  16. chemistry, physics

    In the specific heat measurement does the sample have to be 100 C, or would a lower initial temperature do just aa well? I wrote down it doesn't matter, but i don't know why.
  17. physics

    A ball is thrown straight up and reaches a maximum height of 6.57 m . What was its initial speed? The accelera- tion of gravity is 9.8 m/s2 . Answer in units of m/s
  18. College Physics

    Find the minimum work required to carry a truckload of furniture weighing 1.99 104 N to a third-story apartment, 24.0 m above the truck.
  19. physics

    Evaluate the following statement (T/F/N), explain: If you reduce by half the distance between two point charges, you double the magnitude of electrical force that each exerts on the other.
  20. physics

    top-fuel drag racers are able to uniformly accelerate at 12.9 m/s from rest 97 m/s before crossing the finish line . How much time elapses during the run ?
  21. physics

    A stunt man 60kg jumps down straight down at bozs below 10m from a balcony and he's going down at a speed of 50km/h. What is the force exerted on the boxs?
  22. Physics

    A television tube operates at 20,000V. What is min wavelength for the continuous x-ray spectrum produced when the electrons hit the phosphor?
  23. Physics

    STATE whether you expect the following entities to be in thermal equilibrium with their surroundings under normal circumstances. A. A desk - I think yes B. A person- I think yes C. The walls of a room- I think yes D. The sun- I think no
  24. physics

    a particle a of mass makes perfectly elastic collision with b which is at rest and fly apart in opp directions with same velocity then relation between their masses is
  25. Physics

    A corvette can go from 0~60 mph in 4.3 seconds. If the mass of the car is 1443 kg how much work is required to complete this task (assuming it is on a horizontal road)?
  26. Physics

    Two identical balls roll off the edge of a horizontal table top. One leaves traveling at twice the speed of the other. Which ball hits the floor first? Why?
  27. physics

    With an average acceleration of −1.3 m/s2 , how long will it take a cyclist to bring a bicycle with an initial speed of 13.7 m/s to a complete stop? Answer in units of s.
  28. physics

    A car weighing 1200kg was moving at a speed of 15m/s.breaks were applied and it stopped 6s latter.draw a graph showing the results
  29. physics

    A tungsten target is struck by electrons that have been accelerated from rest through a 24.5-kV potential difference. Find the shortest wavelength of the radiation emitted. (in nm)
  30. physics

    A bullet is fired straight up from a gun with a muzzle velocity of 217 m/s. Neglecting air resistance, what will be its displacement after 9 s? The acceleration of gravity is 9.8 m/s2 .
  31. Physics

    8kg mass moving with a speed of 30 of 30ms-1 is brought to rest in 2.5sec, calculate the magnitude of the constant retarding force
  32. physics

    A 3 meter tall 40 degree inclined plane with a coefficient of friction of .3 with a box sliding from its top has this acceleration and final velocity.
  33. physics

    A sound wave, traveling at 348m/s, is emitted by the foghorn of a tugboat. An echo is heard 1.99 s later. How far away is the reflecting object? Answer in units of m
  34. physics 180

    a gazelle attempts to leap a 1.8 meter fence. assuming a 45 degree takeoff angle, what's the minimum speed for the jump?
  35. Physics

    an aircraft lands on a runway with length of 205 m at a speed of 295 km/h what is the minimum constant deceleration required for a safe landing
  36. physics

    how many electrons must be removed from each of the two 5kg copper spheres to make the electric force of repulsion between them equal in magnitude to the gravitational attraction between them?
  37. physics

    Bob is riding his bike along at 2m/s and drops his 2kg backpack from a height of 1.5 meters. What is the backpacks resulting velocity when it strikes the ground?
  38. Please help with Physics

    I don't understand these questions. Give two examples of common force fields? How is the magnitude of an electric field defined? -I got that it is its strength
  39. Physics

    A baseball is thrown vertically upward with an initial velocity of 20m/s. The maximum height gained by the ball is? I do not understand this problem!
  40. Physics

    With an average acceleration of −2.2 m/s^2, how long will it take a cyclist to bring a bicycle with an initial speed of 14.5 m/s to a complete stop? Answer in units of s.
  41. physics (urgent)

    A flywheel with a moment of inertia of 1.00kg m^2 is rotating at 100 rpm. What torque is required to bring it to rest in 10.0 revolutions?
  42. physics

    The temperature of 7.10 mol of an ideal monatomic gas is raised 15.0 K in an adiabatic process. what is the change ÄK in the average kinetic energy per atom?
  43. physics

    at what inclination should the object be released from rest if it is to reach a maximum horizontal distance of 2m as shown. coeff of friction is 0.37 for all surfaces of contact.
  44. Physics

    What is the difference in blood pressure (mm−Hg) between the top of the head and bottom of the feet of a 1.88m tall person standing vertically?
  45. Physics

    A two-slit pattern is viewed on a screen 1.08 m from the slits. If the two fourth-order maxima are 52.8 cm apart, what is the total width of the central bright fringe?
  46. Physics0

    how to estimate the root mean square speed of hydrogen molecules in the earth's atmosphere in km h^-1? thanks for your help, I'm actually teaching myself physics and that why sometimes I get stuck even with simple questions
  47. Physics

    a 45-kg box initially at rest is being pushed with a force of 950 N along a frictionless horizontal surface. What is the speed of the boz after traveling a distance of 2.0m
  48. physics

    apositive cgarge Q is uniformly distributed around asemicircile of radius R.find the electric field (magneitud and direction)at the center of curvature P.
  49. Physics

    A gram molecule of a gas at 127°C expands isothermally until its volume is doubled. Find the amount of work done and heat absorbed.
  50. physics

    A 1-kg mass hangs by a string from a disk with radius 4.6 cm which has a rotational inertia of 5 × 10-5 kg·m2. After it falls a distance of 0.8 meters, how fast is it going to the nearest hundredth of a m/s?
  51. 12th grade Physics

    Determine the x and y components if a dog walks to the park that is 24m, 30 degrees northwest. Please help i don't know how to go about solving this problem
  52. physics

    how do u find the horizontal force needed to push a wheel that weighs 300N and has a radius of also lies on the stairs of 10m
  53. physics

    an thelet completes one round of circular track of diameter 200m in 40 secomds. wht will be the distance covered t the end of 2min & 20 s.
  54. physics

    how much output I can get if a coil having 100000 turns moves pass a strong 3000 gauss neodymium magnet with 10 m/s velocity only once a time?
  55. physics

    four resistor of resistances 1ohm,2ohm,3ohm,5ohm, are connected in series and afterwards in parallel.calculate the combined resistance in each case
  56. Physics

    What is the dimesnional formula of length, mass, volume, time, radius, force, frequency of evolution, velocity, gravity, tension
  57. physics

    a train is moving at 30m/s when the brakes are applied the retardation is 2m/s (square). find the velocity after 10sec and the time taken for the tree to come to rest
  58. physics

    a proton moves in a circle in a uniform magnetic field of 1T, pointing into the page. Its speed is 1.5 x 10 ^5 m/s. What is the radius of its path? B q v = m v^2/r --------> r = m v/(B q) M=(1.67 * 10-27 ) V= (1.5 * 10^ 5) Q= (1T) B= (1.6 * 10-19 ) is
  59. Physics

    A point (labelled P in the figure) is attached to the rim of a disk of radius 0.2 m, which can turn around an axis through its center. It is rotating counterclockwise with a speed of 2.5 m/s.
  60. Physics

    Determine the energy neded to put 5kg, initially at rest on Earth's surface, into geosynchronous orbit. I get 2.9*10^8 where did I gow wrong?
  61. Honors Physics

    Give some examples of applications that resulted from work done by physicists. The answers I have are: computers, electricity, cars, and television. Are these acceptable?
  62. physics

    What is the required resistance of an immersion heater that will melt 6.39 kg of ice at 0°C in 36 min while operating at 110 V? im not too sure how to do this because delta_T=0. With the equations im using, i get 0 but its not the answer and im not quite
  63. College Physics II

    What is the longest wavelength light capable of ionizing a hydrogen atom in the n = 4 state? i know that Solve h c/L = (Rydberg)/6^2 for L something along those lines... but what am i solving for and what is c and h?
  64. physics

    What hanging mass will stretch a 1.6 meter long, 0.66cm diameter steel wire by 1.4cm.? Need answer in kg. ( this is all that is in the question , no other hints given).
  65. Science - Physics

    Some helium at 20.0psi gauge pressure occupies 40.0ft^3. find its volume at 32.4 psi if the temperature remains constant.
  66. Physics

    use the face that the speed of light in a vacuum is about 3.00 x10^8 m/s to determine how many kilometers a pulse from a laser beam travels in exactly eighteen hours
  67. physics

    A 2.2kg bowling ball with a velocity of 2m/s rolls along a level floor for 30m before coming to a halt. What is the coefficient of rolling friction?
  68. physics

    Geosynchronous communications satellites are placed in a circular orbit that is 3.59 107 m above the surface of the earth. What is the magnitude of the acceleration due to gravity at this distance?
  69. Physics

    A bicyclist climbs a hill 17 m tall and then coasts down the other side without pedaling. If the cyclist’s speed was 2.5 m/s at the top, what is it at the bottom (ignoring friction)?
  70. Physics

    Electrons are ejected from a photoelectric cell with a maximum kinetic energy of 1.20 eV. If the incident light has a wavelength of 410nm, what is the work funtion?
  71. Physics

    A 0.55 kg block slides across a tabletop with initial velocity of 3 m/s and it comes to rest in a distance of 0.53 m. Find the average friction force that retarded its motion.
  72. Quantum Physics

    Suppose a particle has wavefunction ψ(x,t=0)=Aexp(−x22l2). What is the average value (expectation value) of p^, ⟨p^⟩, for this state at t=0?
  73. physics

    What will be the equilibrium temperature when a 245g block of copper at 285 degrees C is placed in a 145g calorimeter aluminum cup containing 825g of water at 12 C ?
  74. physics

    Find the length of a simple pendulum that has a period of 5.00s . Assume g = 9.81 m/s2. Express your answer to three significant figures and include the appropriate units.
  75. physics

    A Martian rover is moving up a hill sloped at 30.0° with the horizontal. If it has a constant velocity of 1.50 meters/second, calculate its vertical displacement after 21.0 seconds
  76. Physics

    Simpson drives his car with an average velocity of 45.1 km/h to the east. How long will it take him to drive 153 km on a straight highway? Answer in units of h
  77. physics

    If a loaded truck that can accelerate at 1 m/s2 loses its load and has four-fifths of its original mass, what acceleration can it attain if the same driving force acts on it?
  78. physics

    With an average acceleration of −0.96 m/s2, how long will it take a cyclist to bring a bicycle with an initial speed of 14.8 m/s to a complete stop? Answer in units of s
  79. physics

    If a Saturn V rocket with an Apollo spacecraft attached has a combined mass of 2.6 105 kg and reached a speed of 11.2 km/s, how much kinetic energy would it then have? __________J
  80. physics

    an object 5cm lenght is placed at distance of 20cm in front of a convex mirror of radius of curvature 30 cm . find the position of the image
  81. Physics

    What is the smallest radius of an unbanked (flat) track around which a motorcyclist can travel if her speed is 25 km/h and the coefficient of static friction between the tires and road is 0.28?
  82. physics

    an experimental jetplane just after takeoff climbs with a speed of 500km/hr at an angle of 37 degrees with the horizontal. At what rate is the plane gaining altitude?
  83. physics

    What is the magnitude of the apparent weight of a 79 astronaut 5200 from the center of the Earth's Moon in a space vehicle moving at constant velocity?
  84. Physics

    By what amount will a 178 m long concrete slab on the Mackinac Bridge contract when going from +39C to -35C? The linear expansion coefficient is 10^-5 per C.
  85. physics

    A car of mass 200g moving at 15.0m/s is accelerated to 25.0m/s in a time of 10.0 seconds determine the accelerating force and calculate the work done on the body

    How does the magnitude of the electrical force between two charged objects depend on the distance between the charges? I really frustrated right now, and I can't figure out the answer too this question. Help pleeease :)
  87. physics

    i know this is stupid most likely but i missed a few weeks of lecture bc i was in hospital and i caught up on most of the notes but certain parts have me confuse, does anyone know how to tell if an electric force is negative or positive?
  88. Chemistry/Physics

    When 1mol of a gas burns at constant pressure, it produces 2430J of heat and does 5kJ of work. Calculate change in H, q, and in kJ?
  89. Physics

    Four masses m1 = 1kg, m2 = 2kg, m3 = 3kg and m4 = 4kg are at the corners of a square of sides 4cm. What is the gravitational potential energy of the system?
  90. physics

    what are the merits and drawbacks of using a person's foot as a standard? keep in mind that it is advantagous that fundamental standards be accessible, invariable, indestructible, and reproducible.
  91. physics

    Zephram is on roller blades on a hill. He starts from rest and skates for 5.5s accelerating uniformly at 3.5m/s2. Show that the distance traveled is 53m.
  92. physics

    a kangaroo jumps to a vertical height of 2.55m.How long was it in the air before returning to Earth? pleaseee anwser it is due in 1 day!!!!
  93. Physics

    in a wire AB of uniform cross section in which a potential gradient of 0.1 V/m exist.If the balancing point is foung to be 180 cm from A then what is the Emf of the cell?
  94. physics

    A ball is thrown straight up with an initial speed of 60 m/s. How high does it go? Assume the accelera- tion of gravity is 10 m/s22 2)How long is it in the air?

  96. Physics Urgent!!!!! I really need help with this

    Sorry to repost this, again, but I still don't understand. Newton’s Law of Gravity specifies the magnitude of the interaction force between two point masses, m1 and m2, separated by the distance r as F(r) = Gm1m2/r^2. The gravitational constant G can be
  97. Physics

    Can someone please answer my question on this paragraph from my physics book regarding basic aerodynamics: "Now we consider a spinning baseball moving through the still air. As the ball spins, it tends to drag air around with it. If the streamlines are
  98. Physics Please Help Today Part 2

    Here's a pic C:\Documents and Settings\Owner\My Documents\My Pictures\physicspic.jpg 0.0100kg particles have been glued to a rod of Length L=6.00cm and negligible mass and can rotate around a perpendicular axis through point O at one end. How much work is
  99. 11 Grade Math-Based Physics

    Could someone check these practice test questions over for me? I'm not good at physics at all, so I would love an explanation. 1. A projectile is shot an angle into the air. Neglecting air resistance... 1a. It's horizontal acceleration is a) 9.8 m/s^2 b)
  100. Physics

    During a track event two runners, Mary, and Alice, round the last turn and head into the final stretch with Mary a distance d = 4.0 m in front of Alice. They are both running with the same speed of v0= 7.0 m/s. When the finish line is a distance L= 45.0 m