Physics!

74,730 results, page 91
  1. physics project

    how to develop a Rube Goldberg machine that will (1) raising a flag on a pole and (2) squeeze a minimum of a 1 cm length of toothpaste on a toothbrush.
  2. physics

    how do u find the horizontal force needed to push a wheel that weighs 300N and has a radius of 30m.it also lies on the stairs of 10m
  3. physics

    why does the flame of a candle always faces upwards though the gravity of earth is pulling everything towards it centre? and though it is faced sidewards?please answer this question as quickly as possible
  4. physics

    The Sun radiates about 4 × 1026 J of energy into space each second. How much mass is released as radiation each second? The speed of light is 3 × 108 m/s. Answer in units of kg
  5. Physics

    A proton and an electron have the same kinetic energy upon entering a region of constant magnetic field. What is the ratio of the radii of their circular path?
  6. physics

    A referee tosses a coin straight up with a velocity of 5.25 m/s, how high does it go above its point of release? (Hint: How fast is it moving at the maximum height?)
  7. Physics

    A bullet fired into a fixed target loses half of its initial velocity in penetrating 15cm. How much further it will penetrate before coming to rest?
  8. physics

    At what projection angle will the range of a projectile equal to 6 times its maximum height? I know its easy but ive been absent and missed class!
  9. physics

    An old-fashioned single-play vinyl record rotates on a turntable at 34.0rpm . What are the angular velocity in rad/s and the period of the motion?
  10. Physics

    At what minimum speed must a roller coaster be traveling when upside down at the top of a circle so that the passengers will not fall out? Assume a radius of curvature of 8.47 m. (in m/s)
  11. 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?
  12. physics

    You work at a garden store for the summer. You lift a bag of fertilizer with a force of 122 N, and it moves upward with an acceleration of 0.760 m/s2.
  13. Physics

    A monoatomic gas expands isobarically.What will be the percentage of heat supplied that increases the thermal energy and that involved in doing work for expansion?
  14. PHYSICS

    A CAR IS BEING DRIVEN BY AFORCE OF 2.5*10POWER10N.TRAVELLING AT ACONSTANT SPEED OF 5m/s,IT TAKES 2 MINUTES TO REACH A CERTAIN PLACE.CALCULATE THE WORK DONE.
  15. physics

    Find the magnitude and direction of the net electrostatic force exerted on the point charge q3 in the figure below, where q = +2.5 μC and d = 28 cm. The picture is of a square. q1=+q, q2=-2q, q3=-3q, q4=-4
  16. Physics(Please help)

    What is the smallest number of whole logs (ñ = 725 kg/m3, radius = 0.0800 m, length = 3.60 m) that can be used to build a raft that will carry four people, each of whom has a mass of 60.0 kg? I do not know how to start this.
  17. Physics

    1a. Two converging lenses, each of focal length 14.4 cm, are placed 60.6 cm apart, and an object is placed 26.9 cm in front of the first. Where is the final image relative to the second lens formed? b. What is the magnification of the system?
  18. 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.
  19. Physics

    A man pulls a 50 kg box with an acceleration of 2m/s^2 across the floor. He applies a 200 N force at an angle of 30 degrees what is the coefficient of the kinetic friction?
  20. 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
  21. 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?
  22. Physics

    A bullet is fired straight up from a gun with a muzzle velocity of 312 m/s. Neglecting air resistance, what will be its displacement after 1.4 s? The acceleration of gravity is 9.8 m/s 2 .
  23. 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.
  24. physics

    What is the magnitude of the apparent weight of a 69 kg astronaut 5200 km from the center of the Earth's Moon in a space vehicle moving at constant velocity?
  25. physics

    a small conducted sphere is attached to the end of an insulating rod .it carries a charge of +5.0*10-9 C. the plates ,which are 4.0 cm apart, are connected to a 50 000 V supply.
  26. PHYSICS ---HELP!

    A man doing push-ups pauses. His mass is 80-kg. Determine the normal force exerted by the floor on each hand and on each foot. a = 40 cm b = 95 cm c = 30 cm W = mg = 784 N
  27. 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.
  28. 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
  29. 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
  30. physics

    You are on a hike in the mountains. You have 3.03 km left to go before your next campsite. The sun will set in 5.2 h. What average speed must you walk to get to camp at sunset? Answer in units of km/h.
  31. Physics

    What is the angular momentum of a 2.4 kg uniform cylindrical grinding wheel of radius 12 cm when rotating at 1800 rpm? How much torque is required to stop it in 4.0 s?
  32. physics

    A toboggan of mass 8.4 is moving horizontally at 18 . As it passes under a tree, 18 of snow drop onto it. We're covering Momentum and collisions, and I have no idea where to start here.
  33. physics

    A toboggan of mass 8.4 is moving horizontally at 18 . As it passes under a tree, 18 of snow drop onto it. We're covering Momentum and collisions, and I have no idea where to start here.
  34. 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
  35. Physics

    Suppose you wish to make a solenoid whose self-inductance is 1.2 mH. The inductor is to have a cross-sectional area of 1.2 10-3 m2 and a length of 0.048 m. How many turns of wire are needed?
  36. physics

    a stone propelled from a catapult with a speed of 50ms-1 attains a height of 100m. Calculate the time of flight and the angle of projection
  37. physics

    A ball of mass moves in a horizontal circular path of radius a with speed v as shown in the illustration below. Find the tension in the cord.
  38. physics

    in ydse, two parallel slits are made 1mm apart and a screen is placed 1m away. what is the fringe seperation when blue green light of wavelength 500 nm is used?
  39. physics

    A novice skier, starting from rest, slides down a frictionless 31.0° incline whose vertical height is 123 m. How fast is she going when she reaches the bottom?
  40. Physics

    How long must a 25 degree ramp be to slow to a momentary stop a runaway truck moving along a truly horizontal highway at 85 miles per hour
  41. 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?
  42. physics

    A person with a mass of 60kg climbs up to a diving board 4 meters above a swimming pool. what is the divers speed when entering the water? A 8.9m/s b 6.2m/s c 4.4m/s d 3.3m/s e 2.1 m/s
  43. Physics

    A baseball is thrown at an angle of 20◦ relative to the ground at a speed of 25.8 m/s. The ball is caught 43.6152 m from the thrower. The acceleration due to gravity is 9.81 m/s2 .
  44. PHYSICS ---HELP!

    A man doing push-ups pauses. His mass is 80-kg. Determine the normal force exerted by the floor on each hand and on each foot. a = 40 cm b = 95 cm c = 30 cm W = mg = 784 N
  45. physics

    How long will it take a sample of polonium-210 with a half-life of 140 days to decay to one-sixty-fourth of its original strength?
  46. physics

    a car whose brakes are locked skids to a stop in 100m from an initial velocity of 20m/s. find the coefficient of sliding friction
  47. 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
  48. physics

    A certain vehicle can accelerate from rest to a speed of 25m/s in a time of 8s.What average power is needed to cause this acceleration?Neglect frictional losses
  49. physics

    An infinitely long wire carrying a current of 2 A is bent at a right angle as shown in the Figure. What is the magnetic field a point P, 10 cm from the corner?
  50. 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
  51. Physics

    A rocket moves upward, starting from rest with an acceleration of 26.3 m/s2 for 5.43 s. It runs out of fuel at the end of the 5.43 s but does not stop. How high does it rise above the ground?
  52. 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
  53. 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?
  54. Physics

    A construction crane's cable lifts a 59.5-kg box upward with an acceleration of 1.38 m/s^2. Find the tension in the rope. 501.585 is incorrect.
  55. 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
  56. Physics Problem 6.9

    Four 8.5 kg spheres are located at the corners of a square of side 0.56 m Calculate the magnitude and direction of the gravitational force on one sphere due to the other three?
  57. 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 ?
  58. Physics

    An advertisment claims that a certain 1200 kg car can accelerate from rest to a speed of 25 m/s in 8.0 s. what average power must the motor supply in order to cause this acceleration?
  59. Physics

    A ball having a weight of 1.5 N is dropped from a height of 4 meters. (Neglect air friction.) How much mechanical energy is "lost" just before it hits the ground?
  60. physics

    Spaceman Spiff's space box wights 60N. its engine exerts a +312N of force at lift-off. what is the acceleration when it lifts off
  61. Physics

    A circular off ramp has a radius of 74 m and a posted speed limit of 50km/h. If the road is horizontal, what is the minimum coefficient of friction needed?
  62. PHYSICS

    With what maximum speed can an unsecured passenger stay in their seat on a Ferris wheel that has a diameter of 12 m. so, this happens when Fn is zero or mg = mv^2/r. v = sqrt(gr) so is it v=sqrt9.8 what would happen with the 12m
  63. physics

    find the effective weight of an astronuat ordinarily weighing 50kg when his rocket moves vertically upwards with 6gm acceleration
  64. physics

    An automobile manufacturer claims that its product will travel 1.2 km in 27 s, starting from rest. What is the magnitude of the constant ac- celeration required to do this? Answer in units of m/s2.
  65. physics

    the 3 lb block A rests on a surface for which the coefficient of kinetic is Mk=.30 determine the distance the 8-lb cylinder B must descend so that A has a speed of Va = 5ft/s starting from rest.
  66. physics

    how does the shotspotter system can determine the location of a shooting, given the initial muzzle report and the fact that this sound moves out in a spherical wavefront?
  67. Physics

    A baseball is thrown horizontally off a cliff with a speed of 7.3 ms-1. What is the vertical distance, to the nearest tenth of a meter, that the ball has fallen after 9.4 seconds?
  68. physics

    A merry-go-round accelerating uniformly from rest achieves its operating speed of 3.4 rpm in 2 revolutions. What is the magnitude of the angular acceleration?
  69. Physics

    A truck of mass 2 tonnes moving at a speed of 25 m/s is brought to rest suddenly in 5 seconds. Calculate the power exerted by the brakes
  70. physics

    a baseball is thrown at an angle of 24 degrees relative to the ground at a speed of 23.4m/s. the ball is caught 41.4798m from the thrower. how long is it in the air?
  71. PHYSICS

    In an archery practice an arrow was realesed from a bow with a velocity of 20m/s it strikes and slopes find at what rate the aarrow was aaccelarated
  72. physics

    an astronaut is competing in mars olympic game her mass is 50 kg she will drive from tower 17 mm above a pool of water how much work in nj must she do to climb 17m
  73. physics

    A diver jumps off a diving board with a speed of 25m/s he returns to the water after 3s. At the top of his dive describe his velocity and his acceleration?
  74. physics

    two particles perform linear simple harmonic motionalongthe same path of length 2A and period T as shown in the graph below. the phase differe3nce between them is -------------
  75. physics

    Two eagles fly directly toward one another, the first at 15.0 m/s and the second at 21.0 m/s. Both screech, one emitting a frequency of 3200 Hz and the other one of 3800 Hz. What frequencies do they receive if the speed of sound is 330 m/s?
  76. physics

    Two eagles fly directly toward one another, the first at 15.0 m/s and the second at 21.0 m/s. Both screech, one emitting a frequency of 3200 Hz and the other one of 3800 Hz. What frequencies do they receive if the speed of sound is 330 m/s?
  77. physics

    Two eagles fly directly toward one another, the first at 15.0 m/s and the second at 21.0 m/s. Both screech, one emitting a frequency of 3200 Hz and the other one of 3800 Hz. What frequencies do they receive if the speed of sound is 330 m/s?
  78. Physics

    Suppose when we look in one half of the sky, the CMBR appears to be at a temperature of 2.725K. What is the peak wavelength in that direction? Are we moving toward or away from the region of space?
  79. physics

    An outfielder throws to the second baseman, a distance of 120ft at a 20degree angle. Whats the min velocity he has to throw the ball to get it to the base?
  80. Physics

    Suppose when we look in one half of the sky, the CMBR appears to be at a temperature of 2.725K. What is the peak wavelength in that direction? Are we moving toward or away from the region of space?
  81. 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?
  82. physics

    Two eagles fly directly toward one another, the first at 15.0 m/s and the second at 23.0 m/s. Both screech, one emitting a frequency of 2600 Hz and the other one of 3800 Hz. What frequencies do they receive if the speed of sound is 330 m/s?
  83. Physics

    A train moving with constant speed of 54kmph moves eastwards for 30min then north for 40min find avg velocity
  84. Physics -- Temp and heat

    Your swimming pool is square and 5.7 m on a side. It is 1.5 m deep in the morning. If the temperature changes by 14°C during the afternoon, how much does the depth of the water increase?
  85. Physics

    Five forces act on an object. (1) 60 N at 90° (2) 40 N at 0° (3) 80 N at 270° (4) 40 N at 180° (5) 50 N at 60° What are the magnitude and direction of a sixth force that would produce equilibrium? Thanks for the help im confused on setting up the f(x)
  86. 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
  87. Physics helllppp

    8] Find the minimum stopping distance for a car moving at 108km/h if the coefficient of static friction between the tires and road is a) 0.9
  88. physics

    A 31.4-kg diver free falls from the diving board and hits the water with a speed of 10.0 m/s. Based on this information, the height of the tower is __________
  89. Chemistry/physics

    Are there two ways of calculating the average kinetic energy of a molecule? Ik that 1/2mv^2 works but for this problem, i don't know the mass or the velocity....
  90. Physics

    Calculate the magnitude of the drag force on a missile 63 cm in diameter cruising at 220 m/s at low altitude, where the density of air is 1.2 kg/m3. Assume C = 0.75.
  91. physics

    four particles of masses 1kg, 2kg,3kg, and 4kg are at vertices of a rectangle of sides a and b.if a=1m and b=2m find the location of the center of mass
  92. Physics

    I have a spring on a horizontal frictionless surface. Initially it is un-stretched and at x = 0 cm. I then pull it back 10 cm and release it. What is the amplitude of the oscillations (the object has mass m)?
  93. Chem/Physics

    Are there two ways of calculating the average kinetic energy of a molecule? Ik that 1/2mv^2 works but for this problem, i don't know the mass or the velocity....
  94. Physics

    If a freely falling rock were equipped with a speedometer, by how much would its speed readings increase with each second IF it were on a planet where g = 20 m/s2? Show all work leading to your answer. g=20 m/s^2 20 m/s V=gt S=g( T ^2) / 2 Is this right ?
  95. physics

    a body is dropped from the roof of a builindgs 10 m high .calculate the time of fall and the speed with which it hits the ground .take g=10m/second sqare
  96. Physics

    If a person weighs 500 N on Earth, what would she weigh on Jupiter, where the acceleration due to gravity is 26 m/s2? Show all work leading to your answer.
  97. physics

    a body is dropped from the roof of a builindgs 10 m high .calculate the time of fall and the speed with which it hits the ground .take g=10m/second sqare
  98. physics

    a diver dives from the top of a 100m cliff. he begins his dive by jumping up with a velocity of 5m/s how long does it takes for him to hit the water below?
  99. Physics to Elena

    Ex=0 ; Ez=0 Ey = 10   sin(3.14x - 6.08e8 t) what is the time-averaged Poynting vector (magnitude and direction) for the position x=y=z=−3 ?
  100. 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?