physics please HELP !

74,851 results, page 77
  1. physics

    The automobile is originally at rest at s = 0. If its speed is increased by dv/dt = (0.05t2)ft/s2, where t is in seconds, determine magnitudes of its velocity and acceleration when t = 18 s.
  2. physics

    Peter Pan is suspended in space. He throws an entire jar of pixie dust to his left. Which way does he move?
  3. physics

    calculate the horizontal force that must be applied to produce an acceleration of 72 m/s^2 for a 0.034 kg punk on a friction less air table
  4. physics

    A boy of mass 50kg runs up a set of stairs of total height of 3.0m.find the work done against gravity
  5. Physics

    Two identical loudspeakers are 2 m apart. A person stands 4.6 m from one speaker and 3.4 m from the other. What is the lowest frequency at which destructive interference will occur at this point?
  6. Physics

    An airplane starts from rest and accelerates at a constant rate if 3.00m/s^2 for 30.0s before leaving the ground. A)How far did it move? B) how fast was it going when it took off?
  7. Physics

    An arrow is launched vertically upward from a crossbow at 98.2 m/s. Ignoring air friction, what is its instantaneous acceleration 4.20 s into the flight?
  8. physics

    With what tension must a rope with length 2.70 and mass 0.150 be stretched for transverse waves of frequency 43.0 to have a wavelength of 0.850 ?
  9. physics

    016 (part 1 of 2) 10.0 points A speedboat increases in speed from 17.9 m/s to 31.8 m/s in a distance 188 m. Find the magnitude of its acceleration.
  10. Physics projectile

    If a body projected vertically upwards, give a graph showing variation in its kinetic energy
  11. physics

    The pendulum swings past the pole 14 times in 21 seconds. The weight of the bob is 10g. Calculate the period?
  12. physics

    A 1600 kg car traveling at a speed of 31 m/s skids to a halt on wet concrete where uk = 0.60. how long are the skid marks?
  13. physics

    A 22cm diameter bowling ball has a terminal speed of 77 m/s. What is the balls mass. I need to get the answer in kg. I can`t figure this one out for some reason. Thanks!!
  14. physics

    A woman with a mass of 65kg climbs a set of stairs that are 3m high. How much gravitational potential energy does she gain? Thank you.
  15. Physics

    By how much shoould a pair of light rays from a common source differ in length to produce destructive interference?
  16. physics

    What is the expected period of beats formed when two tuning forks sound simultaneously and have the frequencies f1= 250Hz and 242Hz?
  17. physics

    Measuring in foot pounds of toque what pressure can the world’s strongest man exert by pulling on an object?
  18. Physics

    I need help figuring this out. I am asked to write about similarities of two different ways of determining the value of g. One of them is using the slope of the line, and one of them is using the average. Each method used the same L and T values.
  19. Physics

    a body of mass 4kg is moving with a momentum of 12kg m/s it's kinetic energy 1:3 then ratio of their velocities Ans:1:3
  20. physics

    Calculate the Coriolis acceleration of an aeroplane flying along the equator due east at a speed of 300m s−1.
  21. Physics

    A man holds a child on his shoulder while watching a football much work is done if the game lasts for 2hours
  22. Physics

    Where did the waste energy go to? A ball rolls off the ramp on the edge of a table heading downward and hits the ground.
  23. physics

    A vector representing 170 N is oriented at 30 degrees with the horizontal. What is the magnitude of the vertical component? Answer in units of N,
  24. Physics

    A box is given a push up a 26.0° incline. When it reaches the bottom again it is only going 0.51 its original speed. Find the coefficient of kinetic friction.
  25. physics

    A projectile is launched at 45 degrees above the horizontal plane, How fast is it moving at the top of its curved trajectory? 141m.s?
  26. Physics

    When an objects acceleration is 0 at an instant t in time, its velocity is 1. zero at t. 2. negative at t. 3. positive at t. 4. not changing at t. My teacher never taught us this, can someone help me figure it out?
  27. physics

    a man walked 32.5m souhward and 78m westward. if it took him 30 minutes to reach his destination.find his average speed?
  28. physics

    A projectile is launched at a speed of 141m/s and an angle of 45 degrees. How fast is it moving at the top of its curved trajectory?
  29. Physics

    How much work is done to the wagon by the girl pulling her brother shown in Figure 4.16, if she travels 25 m? F= (50N), 30 DEGREES ANGLE
  30. Physics

    Five forces act on an object. (1) 63 N at 90° (2) 40 N at 0° (3) 83 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?
  31. physics

    Two freight cars, each with a mass of 3.9 105 kg, collide and stick together. One was initially moving at 3.2 m/s and the other was at rest. What is their final speed in m/s?
  32. Physics

    A 26-lb. force vector that makes an angle of 101° counterclockwise from the -y direction. Determine the x and y components of the following three vectors in the xy plane.
  33. Physics

    The displacement of a harmonic oscillator is given by y = 8.4 sin(14t), where the units of y are meters and t is measured in seconds. What is its maximum velocity?
  34. Physics

    a 4.0 cm high object is placed 5.10 cm from a concave mirror whose redius of curvature is 21.2 cm. Find the inmage distance and the image size.
  35. Physics/Math

    Two vectors are given by a = 3.3i + 6.5j, and b = 2.5i + 4.9j. Find a) a·b = b) (a + b)·b = c) the component of a in the direction of b = a) (3.3x2.5) + (6.6x4.9) = b) (5.8x2.5) + (11.4x4.9)= c) (a·b)/(magnitude of b)= Great! I got it :)
  36. Physics

    A 3kg block is resting on a table with a coefficient of friction of 0.4. It is now pushed with a force of 15n. What is the acceleration of the book?
  37. physics

    How many revolutions per minute would a 15 -diameter Ferris wheel need to make for the passengers to feel "weightless" at the topmost point?
  38. physics

    the work function of zinc is 3.6ev what is maximum enegy photoelectron by ultraviolet wave of light 3000angstrome
  39. physics

    Calculate the pressure exerted on the floor by the heel if it has an area of 1.45 cm2 and the woman's mass is 58.0 kg. Express the force in N/m2 and lb/in
  40. physics

    A sled is initially given a shove up a frictionless 32.0 incline. It reaches a maximum vertical height 1.50 higher than where it started.
  41. physics little folks

    a mass is attached at the spring perform SHM with frequency of 15 hz find the acceleration when displacement is 1.6cm
  42. physics

    The coldest and hottest temperatures ever recorded in the United States are -83°F and 135°F, respectively. What is the speed of sound in air at each temperature?
  43. physics

    A rocket is fired with an initial velocity of 200m/s at an angle of 60' to the horizontal.Find (1)the maximum height reached.
  44. physics

    Who developed modern periodic table? Descibe particle arrangements & movement for each phase of matter. (Thank you for helping me)
  45. Physics

    A 60-kg person begins to accelerate upwards on an elevator at a rate of 3 m/s^2. What does the scale read at this time? My answer: 768 N
  46. Physics

    A soccer player launches a ball at an angle of 40 degrees, with an initial velocity of 23 m/s. What are the horizantal and vertical for this problem??
  47. physics

    two ropes are tied on a post and applied with forces of 8 and ion.If the amgle between them is 60degrees. Find the resultant vector
  48. physics

    A softball bat is rotating at 460 rotations per minute at contact with the ball. What is the angular velocity in radians?
  49. Physics

    Find the average velocity over the time interval from 1 to 3 seconds. Express your answer in meters per second to the nearest integer.
  50. physics

    How long does it take for the ball to hit the ground 7 meters below if it's thrown straight up wit intial velocity of 2 m/s squared?
  51. Physics

    An olympic hurdler is in a race. He is running at 10 m/s and jumps over a hurdle. How high did he jump if he was moving at 1m/s as he crossed the fence?
  52. physics

    Calculate the time required for an astronaut to free-fall 50 m on the Moon. Please show and explain steps answer is 7.9s

    Calculate the maximum height the tank shell reaches using the initial speed (18 m/s), half-time(1.8), and angle(75).
  54. Physics

    What is the minimum work in joules needed to push a 1840 kg car 14.0 m up a 12.5 degree incline? (Ignore friction.)
  55. physics repost

    A 1.00-kg ball is attached to a string of 0.50 m and swung in a horizontal circle with a velocity of 2.00 m/s. Find the centripetal acceleration. ac=v^2/r = 2.00^2/.50 = 8.0 m/s^2
  56. physics

    calculate the force exerted on a rocket given that the propelling gases are expelled at a rate of 1000 kg/s with a speed of 60,000 m/s.
  57. Physics

    A bomb explores in mid air into two equal fragments.what is the angle between their direction of motion? Ans:- 180°
  58. Physics

    A 84.0-kg airplane pilot pulls out of a dive by following, at a constant speed of 163 km/h, the arc of a circle whose radius is 312.0 m.
  59. Physics 1

    A 1400 kg car traveling at a speed of 34 m/s skids to a halt on wet concrete where μk = 0.50. How long are the skid marks?
  60. physics

    what is reaction product when ethene is treated with steam using phosphoric acid as catalyst at 300 degrees celcious
  61. physics

    If a cyclist traveling at 14.0m/s skids to a stop in 5.60 s, determine the skidding distance assume uniform acceleration? Answer is 39.2m
  62. physics

    three point charges are located at the corners of a right triangle where q1=q3= 5uC,Q2= -2uC and r =10cm.(angle q1 q2q3=90 and q1q3=r)
  63. Physics

    An American bald eagle heads south at 5.5 m/s, but encounters a wind blowing from the east at 1.9 m/s. By how many degrees will she be blown o course?
  64. physics

    A loaded truck can accelerate at 4.1 m/s 2 . It loses its load so that it is only 0.8 as massive. By what factor must the acceleration change for the same driving force?
  65. Physics

    A tyre is suddenly brust when it was pumped to a presure of 4 atm at 20 degree celsius. Calculate the final temperature.

    (a) how long it took King Kong to fall straight down from the top of a 210 m high building s (b) his velocity just before "landing"
  67. physics - forces

    Calculate the velocity of a satellite moving in a stable circular orbit about the Earth at a height of 2600 km.

    Eight charges (50μC each) are arranged on the corners of a cube side length 1 cm. What is the magnitude of the force on each charge in Newtons?
  69. Physics

    with what minimum speed must a ball be thrown straight up in order to reach a height of 34 meters above the launch position?
  70. physics

    three point charges are located at the corners of a right triangle where q1=q3= 5uC,Q2= -2uC and r =10cm.(angle q1 q2q3=90 and q1q3=r)
  71. Physics

    A projectile is fired straight up at a speed of 13 m/s. How long does it take to reach the top of its motion? The acceleration due to gravity is 9.8 m/s2 .
  72. physics

    Geostationary satellites are placed on orbits of radius 4.2×10^4m use this information to deduce g, the acceleration of freely falling body, at this height.
  73. physics

    How long would it take to bring a 318 kg car moving at 11.2 m/s to a complete stop if a 602.8 N breaking force is applied?
  74. physics

    Describe briefly how the volume of a given mass of water changes when it is cooled from 7 ^0 C to 1^0 C use the terms increase, decrease and maximum or minimum
  75. physics

    What is the minimum work function for a metal for visible light (wavelengths between 400 and 700 ) to eject photoelectrons?
  76. physics

    A bat at rest sends out ultrasonic sound waves at 51.1 and receives them returned from an object moving directly away from it at 22.3 .
  77. Physics

    Two tuning forks are struck at the same time; one with a pitch of 410Hz one a frequency of 500Hz. How many pitches do you hear and what are the frequencies?
  78. physics

    a long jump athlete take off at 25 degree with the horizontal and achieves a jumping distance of 9.12 m. Calculate initial take off speed.
  79. physics

    During an Olympic bobsled run, the Jamaican team makes a turn of radius 7.9 m at a speed of 97.4 km/h. What is their accelaration in g-units?
  80. Physics

    Calculate the skid_to_stop distance of a car traveling on a road at 100 kilometers per hour with a coefficient of friction of 0.68...
  81. physics

    Describe briefly how the volume of a given mass of water changes when it is cooled from 7 ^0 C to 1^0 C use the terms increase, decrease and maximum or minimum
  82. physics

    Calculate the escape velocity on surface of earth of radius of moon is 1740km and Massis7.4 *10to the power 22
  83. physics

    why is it that drivers place cement blocks and other heavy items in the trucks of their vehicles? (think of friction and normal force)
  84. Physics

    If you are at the top of a toboggan run that is 44.3 m high, how fast will you be going at the bottom, provided you can ignore friction between the sled and the track?
  85. physics help please

    An airplane that can fly at 300 km/hr is flying at 210 when it is hit by a wind of 125 km/hr at 110. What is the new velocity of the plan?
  86. physics

    draw a particle model and a motion diagram for A bike travels at constant speed of 4.0 m/s for 4 s then slow down to come at rest in 3 s.
  87. physics

    An object 4cm high is placed 25cm from a covering lens of focal length 15cm the image height is
  88. physics

    a circuit consist of an inductance of 0.05H, a resistance of 20ohms , a capacitor of 100uF and an angle of 100cos200t. find (i) and (q) given that q=0,and i=0 at t=0.
  89. Physics

    If you were to jump from an airplane at an altitude of 15000 ft. and fall toward the Earth at 100 mph how long would it take to reach the surface?
  90. physics

    A splash is heard 3.12s after a stone is dropped into a well 45m deep.the speed of sound in air is(g=10m/s2)
  91. physics

    During an Olympic bobsled run, the Jamaican team makes a turn of radius 7.6 m at a speed of 96.6 km/h. What is their acceleration in terms of g?
  92. physics

    A 78-kg parachutist, in the first few seconds of her jump, accelerates at a rate of 7.4 m/s2 [down]. Calculate the force she experiences due to air resistance.
  93. Physics

    Can someone help me with finding out the magnitude of the gravitational force a person with a mass of 67.5 kg would experience while standing on the surface of Earth? Thanx in advance.
  94. physics

    If the breakers at a beach are separated by 5m and hit shore with frequency of 0.3Hz, at what speed are they travelling? Please show all work, Thank you
  95. Physics

    Show that 480 W of power is expended by a weightlifter when lifting a 60-kg barbell a vertical distance of 1.2 m in a time interval of 1.5 s.
  96. physics

    In the following list of periodic waves, which one is independent of the others: frequency, wavelength,speed,amplitude? Plese show all work Thank you
  97. physics

    what sould be the angular speed with which the earth have to rotate on its axis so that a person on the equator would weight 3/5th as much as present..??
  98. physics (science)

    A body travels from rest with acceleration 8m/s square . Find its velocity when it has covered a distance of 100m
  99. physics

    Five forces act on an object. (1) 57 N at 90° (2) 40 N at 0° (3) 77 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?
  100. physics

    Thirty microcoulombs of NEGATIVE charge experiences an electrostatic force of 27. mN. What is the magnitude and direction of the electric field?