physics please HELP !

74,851 results, page 100
  1. physics

    A 95 N block rests on a table. The sus- pended mass has a weight of 22 N. What frictional force is required to keep the blocks from moving? Answer in units of N.
  2. physics

    I need help with conversions: Vera survived the longest fall on record without a parachute. she fell 6miles, 551 miles. whats her distance in yards?
  3. PHYSICS

    Calculate the stress, strain and young's modulus of a wire with a cross-sectional area of 3 x 10^-7 m^2 and a length of 0.6 m that is stretched to a distance of 1.2 x 10^-3 by a 120 N force.
  4. physics

    a 1240 kg automobile stops in a distance of 41m. if initial velocity was 22.5m/s, what force did the road exert on the car to stop it? Answer pls... Thank You
  5. physics

    Three positive point charges of 3.0 nC, 6.0 nC, and 2.0 nC, respectively, are arranged in a triangular pattern, as shown below. Find the magnitude and direction of the electric force acting on the 6.0 nC charge.
  6. physics

    A long jumper leaves the ground at an angle of 22.1◦ to the horizontal and at a speed of 10 m/s. How far does he jump? The acceleration due to gravity is 9.8 m/s2 . Answer in units of m
  7. Physics

    A basketball is thrown at 45° to the horizontal. The hoop is located 6.2 m away horizontally at a height of 1.1 m above the point of release. What is the required initial speed? I know that I need to use d = vit + (0.5)at^2, but I then get stuck. Thanks!
  8. Physics

    Calculate the electric force between these two electrons. The value of the Coulomb constant 9 × 109 N · m2/C2 and the elemental charge is 1.6×10−19C. Answer in units of N (Newtons)
  9. Physics

    All of the following are advantages of using the services of an investment company except: A. professional management. B. diversification. C. ease in selling shares. D. insurance protection against loss of principal. D?
  10. physics

    The New River Gorge bridge in West Virginia is a 518 m long steel arch. How much will its length change between temperature extremes -19°C and 39°C? (answer in cm)
  11. physics

    A ball is thrown vertically upward with a speed of 27.3 m/s from a height of 2.1 m. How long does it take to reach its highest point? The acceleration of gravity is 9.81 m/s2. Answer in units of s
  12. physics

    two boys start running straight towards each other from two points that are 100m apart. one runs with a speed of 5m/s, while other moves at 7m/s.how close are they to the slower one's starting point when they meet?
  13. Physics

    A ball of mass 8 kg falls from rest from a height of 100 m. Neglecting air resistance, calculate its total energy after falling a distance of 40 m.
  14. physics..

    What is the maximum height achieved if a 0.800 kg mass is thrown straight upward with an initial speed of 40.0 m·s–1? Ignore the effect of air resistance.
  15. Physics, still don't get it!

    Suppose a monatomic ideal gas is contained within a vertical cylinder that is fitted with a movable piston. The piston is frictionless and has a negligible mass. The area of the piston is 3.06 10-2 m2, and the pressure outside the cylinder is 1.02 105 Pa.
  16. physics - additional info added

    SEE ADDITIONAL INFO ADDED Using the motor principle explain why a motor is rotating in the direction indicated. I seriuosly have no idea, please help explain this theory to me. PHYSICS - drwls, Saturday, February 6, 2010 at 2:15pm To help you answer that
  17. trig/physics

    Three positive particles of equal charge +11.o micro C, are located at the corners of an equilateral triangle of sides 15.0cm. Calculate magnitude and direction of the net force on each particle. DUUUUUUUUUH! THIS IS SO EASY! LOOK IN YOUR BOK, IDIOTIC
  18. Physics

    A light string, connects blocks 1 and 2 of masses m1 and m2. These blocks are further connected to a block of mass M by another light string that passes over a pulley of negligible mass and friction. Blocks 1 and 2 move with a constant velocity v down the
  19. Probability

    The probability that a student passes a physics test is 2/3 and the probability that he passed both physics test and an english test is 14/15. The probability. The probability that he passes at least one test is 4/5. What is the probability that he passes
  20. Science, Physics, math, calculus

    Pool players often pride themselves on their ability to impart a large speed on a pool ball. In the sport of billiards, event organizers often remove one of the rails on a pool table to allow players to measure the speed of their break shots (the opening
  21. Physics (Center of Gravity)

    In a lab in my physics class, we were supposed to find the CG of my physics teacher. My partner and I had him lie flat on a wooden (assumed uniform) board that was resting on top of two PVC pipes at either end. Since the PVC pipes acted as the base of
  22. physics homework

    can you please check my answers? 10. when rewinding a an audio tape or vdieotape, one reel winds fastest at the end. which reel is this? why does it speed up? -The reel is the left and it speeds up because of its greater rotational intertia is near the
  23. Physics

    Please help me with these three questions,they deal with coefficient of friction 1) A car rounds a turn of radius 25m at a speed of 20m/s. Find the coefficient of friction neccessary to keep the car on the road 2) A man is attempting to slide a piece of
  24. Physics

    Pool players often pride themselves on their ability to impart a large speed to a pool ball. In the sport of billiards, event organizers often remove one of the rails on a pool table to allow players to measure the speed of their break shots (the opening
  25. Physics

    Someone posted the question below, stating that they knew the answer to part A but needed help with part B. Well even with the answer for A, I can't figure it out! Can you take a step back from the question below to show me the steps for solving part A?
  26. Physics

    ool players often pride themselves on their ability to impart a large speed to a pool ball. In the sport of billiards, event organizers often remove one of the rails on a pool table to allow players to measure the speed of their break shots (the opening
  27. Physics

    Hi. I am Walter White. I am good at chemistry but suck at physics. Can you help me? ---------------------------------------- Bob is traveling in a very fast space (v=0.8c) away from Alice, who is sitting still in an observatory watching him through a very
  28. physics

    im not sure how to do this question 80 N and 60 N force act concurrently on a point. find magnitude of the vector sum if the forces pull -in the same direction -in opposite direct. -at right angles to each other thanks
  29. Physics

    With a 1220–W toaster, how much electrical energy is needed to make a slice of toast (cooking time = 1.3 minute)? At 12.1 cents/kW·h, how much does this cost? (You do not need to enter any units.)
  30. physics

    A rocket moves upward, starting from rest with an acceleration of 28.5 m/s 2 for 3.09 s. It runs out of fuel at the end of the 3.09 s, but does not stop. How high does it rise above the ground? Answer in units of m
  31. Physics

    A baseball is thrown upward with a velocity of 15m/s. How fast is it moving after 2 seconds? I have no Idea how to begin and the formula he gave us isn't even related to the question at all. (V=vi+at)
  32. physics

    If we apply 300 kJ of heat to 2500 moles of air at constant pressure, what is the change in internal energy? Answer a. 214 kJ. b. 100 kJ. c. 180 kJ. d. 75 kJ.
  33. physics

    A ball of mass 1kg is thrown upwards and reaches a maximum height of 4m.Calculate the work done by the force of gravity during vertical displacement.Take g=10m/s
  34. physics

    i do not get this question at all and if u could help it'd be a real HUGE help. solve these equations (sorry i do not have the symbols so i will just write the words out. sorry again for any inconveniance. ): time= 2pi x squareroot of length/gravity ....i
  35. Physics

    With an average acceleration of negative 1.2m/s squared, how long will it take a cyclist to bring a bicylcle with an initial speed of 6.5 m/s to a complete stop? answers are: either 2.0, 5.4. 0.18 or -1.8s Please help-I am totally confused
  36. physics

    A cannon is fired from a cliff 200 m high downward at an angle of 30o with respect to the horizontal. If the muzzle velocity is 34 m/s, what is its speed (in m/s) when it hits the ground?
  37. physics

    A remote control toy car starts from rest and moves with constant unkown acceleration. After half a second it has travel 0.65m. How far has it traveled after 3 seconds?
  38. Physics

    An object is placed on a frictionless inclined plane, and will accelerate at a constant rate. Determine the amount of acceleration due to gravity both parallel and perpendicular to the incline.
  39. Physics

    Compute the entropy change of a system consisting of 1kg of ice at 0•C which melts (reversibly) to water at the same temperature. The latent heat of melting is 79.6 Cal/g
  40. PHYSICS

    Two railroad cars, each of mass 7600KG and traveling 85KM/H in opposite directions, collide head-on and come to rest. How much thermal energy is produced in this collision?
  41. Physics

    Electrical conductivity in liquid solutions depends on the presence of free 1) neutrons 2) protons 3) molecules 4) ions explain please I really don't understand this question
  42. Physics

    Find the work done by a white collar criminal as he pulls his 34 kg bag of booty 2.7m forward at an angle of 61 degrees with the floor. The man is pulling with a force of 19.4 N.
  43. Physics 2

    A 6 cm high object is placed 43ncm from a converging lens of focal length 24 cm. Find the image’s position and draw a ray diagram approximately to scale.
  44. Physics

    Sherlock Holmes examines a clue by holding his magnifying glass (with a focal length of 26.5 cm) 15.1 cm away from an object. Find the image distance. Answer in units of cm
  45. physics

    A drag racer starts her car from rest and accelerates at 9.0 m/s2for the entire distance of 105.0 m. What is its speed at the end of the run? Answer in units of m/s.
  46. Physics

    Hydro Quebec charges clients by the kilowatt hour. Is this a unit of power, energy or force? If you consume 500kWh per month how would this be expressed in SI units?
  47. physics

    A 7 kg block slides on a horizontal frictionless surface with a speed of 1.2 m/s. It is brought momentarily to rest when it hits a bumper that compresses a spring. The acceleration of gravity is 9.8 m/s^2.
  48. Physics

    A linear spring of stiffness k is designed to stop the 20-Mg railroad car traveling at 8 km/h within 400mm after impact. Find the smallest value of k that will produce the desired result.
  49. Physics

    A 45-kg skater rounds a 5.0-m radius turn at 6.3 m/s. (A.) What are the vertical and horizontal components of the force the ice exerts on her skate blades? (B.) At what angle can she lean without falling over?
  50. physics asap

    A 1000-kg car moving at 10 m/s brakes to a stop in 5 s. The average braking force is? On this question I asked my teacher I am suppose to get 2000 N and I don't get how to get it.
  51. Physics

    At a given instant three electrons, in vacuum, happen to lie on a straight line. The first and second are separated by 3.00x 10-6 m, while the second and third are 8.00 10-6 m apart. What is the magnitude of the net electrostatic force on the middle
  52. physics

    many automobile passengers suffer neck injuries when struck by cars from behind. how does newtons law of inertia apply here?why would a headrest help guard against whip-lash
  53. Physics

    A cannon is fired at 30 degrees above the horizontal with a velocity of 200 m/s from the edge of a 125 m high cliff. Calculate where the cannonball lands on the level plain below.
  54. Physics

    A 2000 {\rm kg} car traveling at a speed of 13 {\rm m/s} skids to a halt on wet concrete where mu_k = 0.50. How long are the skid marks? I tried doing this many times and each answer is wrong. Can someone help?
  55. physics

    hey, if someone could please help me solve this: object kicked at 45 degree and travels 82 m b4 hitting the ground. what was its vo? how long was it in the air? how high did it go? tell me if this is right, i got 740m for the height... doesnt sound right..
  56. physics

    A stone of mass 0.7kg is projected vertically upward with a speed of 5m/s.calculate the maximum height reached. [Take g=10m/s^2 and neglect air resistance]. "
  57. Physics ib

    What is the way to set up an electric circuit with a filament lamp, switch, battery, ohmmeter, voltmeter and variable resistor as to have the most optimal measurement for the current and voltage?
  58. Physics

    At what positions is the speed of a simple harmonic oscillator half its maximum? That is, what values of x / X give v = ±vmax/2 , where X is the amplitude of the motion? Hello, I am so confused about this question. I am not really sure where to start.
  59. physics

    A bullet is fired straight up from a gun with a muzzle velocity of 225 m/s. Neglecting air resistance, what will be its displacement after 6.1 s? The acceleration of gravity is 9.8 m/s2 . Answer in units of m
  60. Physics: Sound Waves

    Two organ pipes, open at one end but closed at the other, are each. 1.14 m long. One is now lengthened by 2.00 cm. Find the frequency of the beat they produce when playing together in their fundamental.
  61. physics

    A football is thrown upward at a(n) 23◦ angleto the horizontal. The acceleration of gravity is 9.8 m/s To throw a(n) 52 m pass, what must be the initial speed of the ball? Answer in units of m/s
  62. physics

    a 8 kg ball is thrown upward with an initial speed of 20 m/s. suppose there is a constant air resistance of 30N opposing the motion during it entire up and down path. what is the acceleration on the way up and on the way down?
  63. physics

    A child rides a ferrisvwheel for 3.5 minutes. If a rotation covers 986 feet and it rotates 1.5 times per minute, what is the velocity of the ride? Whats the mistake?
  64. physics

    Engineers are developing new types of guns that might someday be used to launch satellites as if they were bullets. One such gun can give a small object a velocity of 2.5 km/s while moving it through a distance of only 1.9 cm.
  65. Physics

    A force of 10N applied normal to the wall can just prevent the sliding of a wooden block. If co-efficient of static friction is 0.2.Find the weight of the body.
  66. Physics

    What net braking force must be applied to stop a car with a mass of 900 kg initially travelling at a velocity of 100 km/h within a straight-line distance of 50 m?
  67. Physics

    Jill and her friends have built a small rocket that soon after lift-off reaches a speed of 900 m/s How high above the Earth can it rise? Ignore air friction. h=? m
  68. physics

    50kg iceskater turns a bend at 7m/sec. if the radius of the curve is 5 meters, what is the centripetal force provided by the friction between the blade of the skate and the ice?
  69. Physics (I have a test tomorrow)

    What power is required to accelerates a 1980kg car from 30km/h to 70km/h against a constant force of resistance of 750N over a distance of 85m. Thank you for your help!
  70. Physics

    Three objects with masses m1= 36.5 kg m2= 19.2 kg m3= 12.5 kg Are hanging from massless ropes that run over a frictionless pulleys. If the system is released from rest, what is the magnitude of the acceleration in m/s^2 of mass m1? ___________________ O O
  71. physics

    Two ice skaters hold hands and rotate, making one revolution in 2.4 s. Their masses are 60 kg and 70 kg, and they are separated by 1.5 m. Find the angular momentum of the system about their center of mass.
  72. physics

    A truck sounds its 810 hz horn as it drives outside a house at 30mph. But the occupant's ear detects a frequency of 780hz. What is the temperature of the air at this location?
  73. physics

    A object is throw up with a speed of 25m/s. suppose that the gravity is 10m/s^2. Define the position and the velocity of the particle for the following times: 1second, 4second and 10second
  74. physics

    In the past, ships often carried small cannons that wer used when approaching shore in a dense fog to estimate the distance to the hidden land. How would this work?
  75. physics

    How deep can a snorkel diver dive if the maximum gauge pressure on the thorax cannot exceed 10.9 kPa? Hint: density of seawater = 1.015g/cm3
  76. physics

    A object is throw up with a speed of 25m/s. suppose that the gravity is 10m/s^2. Define the position and the velocity of the particle for the following times: 1second, 4second and 10second
  77. Physics

    A catcher “gives” with the ball when he catches a 0.179 kg baseball moving at 16.5 m/s. If he moves his glove a distance of 2.25 cm, what is the average force acting on his hand? Answer in units of kN.
  78. Physics

    Calculate the angular momentum and kinetic energy of a solid uniform sphere with a radius of 0.120 m and a mass of 14.0 kg if it is rotating at 6.00 rad/s about an axis through its center..
  79. PHYSICS

    A 0.500 kg wheel that has a moment of inertia of 0.015 kg m^2 is initially turning at 30 rev/s. it starts to rest after 163 revolution. how large is the torque that slowed it?
  80. physics

    A object is throw up with a speed of 25m/s. suppose that the gravity is 10m/s^2. Define the position and the velocity of the particle for the following times: 1second, 4second and 10second
  81. Physics

    What is the change in angular momentum of a planet with radius R if an asteroid mass m and speed v hits the equator at an angle from the west, 40 degrees from the radial direction?
  82. Physics

    A rocket moves upward, starting from rest with an acceleration of 28.3 m/s2 for 5.50 s. It runs out of fuel at the end of the 5.50 s, but does not stop. How high does it rise above the ground? Answer in units of m
  83. Physics

    Three objects with masses m1= 36.5 kg m2= 19.2 kg m3= 12.5 kg Are hanging from massless ropes that run over a frictionless pulleys. If the system is released from rest, what is the magnitude of the acceleration in m/s^2 of mass m1? ___________________ O O
  84. Physics

    A spectrometer uses a grating with 11600 lines/cm. Find the angle at which red light, 632.3 nm, has the first-order bright band. Answer in units of degrees.
  85. physics

    an ideal monatomic gas is allow to expand slowly until its presssure is reduced to exactly half its original value. By what factor does the volume change if the pressure is (1) isothermal (2) adiabatic
  86. physics

    A hippo has a mass of 6000kg. When standing on 4 feet, how much pressure is exerted on the ground? Assume each foot has an area of 0.10 square meter. Show your work.
  87. physics

    At what rate must a cylindrical spaceshiprotate if occupants are to experience simulated gravity of g/4? Assume the spaceship's diameter is 36 m, and give your answer as the time needed for one revolution.
  88. physics

    a point charge q is located btween two earthed intersecting conducting planes that are inclined at 60 degree to each other .determine the number of image charges and their location .
  89. physics

    A hippo has a mass of 6000kg. When standing on 4 feet, how much pressure is exerted on the ground? Assume each foot has an area of 0.10 square meter. Show your work.
  90. physics

    A man whose mass is75kg walks up a stairs of 12steps each 20cm high in 5seconds.calculate the power expended in watts.[assume g=10m\s2
  91. physics

    Suppose David Ortiz hits a home run which travels 361. feet (110. m). Assuming it left the bat at 50.°, how fast was it hit?
  92. Physics

    A ball is thrown vertically upward with a speed of 25.0m/s.take acceleration due to gravity 10m/s-2. A how high does it rise B how long does it take to reach its highest point?
  93. physics

    A hippo has a mass of 6000kg. When standing on 4 feet, how much pressure is exerted on the ground? Assume each foot has an area of 0.10 square meter. Show your work.
  94. Physics

    A tennis player makes a return at a speed of 18m/s and at a height of 3m to land in the court at a horizontal distance of 12m from her. What are the possible angles of projection of the wall
  95. Physics

    v(y)=v with letter y below normal line. "Explain why you can use the formula v(y)=g(t/2) to calculate the initial vertical velocity." My teacher claimed he explained the answer to this, but I didn't catch it. I would appreciate any help I get. THANKS!!!
  96. physics

    The feature that our eyes are most sensitive to seeing is which of the following? A) edges or boundaries.B) images that fall on the blind spot.C) gray areas.D) anything at the periphery.E) all light of moderate intensity.
  97. Physics

    Use the Work-Energy Theorem to show that an object with initial velocity vo will travel a distance d across a rough horizontal surface before stopping, where d = vo2/(2mKg).
  98. physics

    an aeroplane fly upward at 100m/s at an angle 50.when it reached altitude of 900m,a package is throw down. calculate the distance along the groundfrom the point of released
  99. physics

    A cannonball is fired with an angle of 40 degree above the horizontal.If the velocity when it hits the ground is 80 m/s FIND a.Viy b.time of travel c.max height d.range
  100. Physics

    During a baseball game, a batter hits a pop-up to a fielder 83 m away. The acceleration of gravity is 9.8 m/s^2. If the ball remains in the air for 6.5 s, how high does it rise? Answer in units of m