physics please HELP !

74,851 results, page 92
  1. physics

    What is the self-inductance of an air-core solenoid,1m long and 0.05m in diameter,if it has 1400 turns?(a)5.23mH(b)4.84mH(c)3.63mH(d)2.42mH
  2. physics

    A rocket moves upward, starting from rest with an acceleration of 29.4 m/s2 for 5.65 s. It runs out of fuel at the end of the 5.65 s but does not stop. How high does it rise above the ground?
  3. Physics

    W.K.T, Magnetic Force qvB=mv^2/r ... n we know how to prove it too.... But how to show that the radius of curvature of the circular path is proportional to the linear momentum of the charge ?
  4. 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?
  5. physics

    A train is moving with an initial velocity of 30 m/s the breaks are applied so as to produce uniform acceleration of minus 1.5m/s Calculate the time in which it will come to rest
  6. physics homework

    0.2kg mass hangs at the end of the wire. what is the tension if the ball is then whirled around in a horizontal circle with tangential velocity of 5m/s
  7. 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)
  8. physics

    A window air conditioner consumes 900 W of electric power and has COP = 2.9.If it runs continuously for 24 h , how much heat gets removed from the house?
  9. Physics

    A 52kg ice hockey player moving at 11m/s slows down and stops over a displacement os 8.0m. Calculate the net force of the skater.
  10. physics

    A rocket moves upward, starting from rest with an acceleration of 28.1 m/s2 for 4.76 s. It runs out of fuel at the end of the 4.76 s but does not stop. How high does it rise above the ground?
  11. 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?
  12. physics

    When a 1150 kg space rocket lifts off of ground. How many joules of energy has been provided by its engine during the time in which it achieves a speed of 180 m/s.
  13. physics

    a stone is projected vertically upward and reaches a maximum height of 20m before it returns to the thrower find the total time taken
  14. Physics

    Use the first law of thermodynamics to determine the amount of heat change, Q, and whther it was added to or removd from the system. W=225J Delta U=600J Q=?
  15. physics

    A ball of mass m is projected with a speed u at an angle theta with horizontol. Find the change in momentum after time t and when it reaches the ground
  16. Physics

    A monochromatic wavelength 600nm passed through a singlde slit which has a width of 0.8mm. A,calculate the distance between six and nineth bright frings.
  17. physics

    If the height of the water slide in the figure below is h1 = 1.55 m and h2 = 1.35 m, and the person's initial speed at point A is 0.593 m/s, at what location does the swimmer splash down in the pool?
  18. Physics

    What is the difference in blood pressure (mm−Hg) between the top of the head and bottom of the feet of a 1.82m tall person standing vertically?
  19. Physics

    Find the approximate gravitational red shift in 500 nm light emitted by a compact star whose mass is that of sun but whose radius is 10 km.
  20. 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.
  21. Physics

    Find the approximate gravitational red shift in 500 nm light emitted by a compact star whose mass is that of sun but whose radius is 10 km.
  22. 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.
  23. 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
  24. physics

    Determine the frequency and period for a pendulum of length 250cm, mass of 500g, and amplitude of 25cm I don't understand how to do this, help would be appreciated! Thank you
  25. physics

    A 1000 Kgs Vehicle moving with a sppeed of 20 meter per sec. is brought to rest in a distance of 50 metres. find the acceleration
  26. physics

    A novice skier, starting from rest, slides down a frictionless 33.0° incline whose vertical height is 127 m. How fast is she going when she reaches the bottom?
  27. Physics

    A weightlifter raises a 90k-g barbell from the floor to a height of 2/2 m in 0.6 s. What was his average power output during his lift? Sorry I wrote it wrong the first time!
  28. Physics

    Find the approximate gravitational red shift in 500 nm light emitted by a compact star whose mass is that of sun but whose radius is 10 km.
  29. physics multiple choice MCQ 5- i need help please @all respective sir & bro

    The unit of time in S.I. units is? a. second b. minute c. hour d. day e. year
  30. physics

    As a young boy swings a yo-yo parallel to the ground and above his head, the yo-yo has a centripetal acceleration of 250m/s^2. If the yo-yo's string is 0.50 m long, what is the yo-yo's tangential speed?
  31. Physics

    A 1.8 kg rectangular air mattress is 2.46 m long, 1.23 m wide, and 0.189 m thick. What mass can it support in water before sinking? Answer in units of kg.
  32. 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.
  33. Physics

    Calculate the magnetic flux density in air at a point 15mm from a long straight wire carrying a current of 100A
  34. physics

    A stone is thrown downward into a well with an initial speed of 5.00 m/s. The sound of splash is heard 1.50 s later. Find the depth of the well if the air temperature is 15.0 ˚C?
  35. physics

    A 58 kg skier has a speed of 9.5 m/s at point A. She then encounters a 1.75 m deep dip in the snow's surface that has a circular cross section with a radius of curvature of 12 m.
  36. 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
  37. physiçs

    What precautions shouĺd i apply when doing a coefficieñt of friction.force applied to a blocķ on a hořizontal plane?
  38. 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 -------------
  39. 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
  40. Physics please help!

    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?
  41. Physics

    Rotating initially at 1800 rpm, a wheel with a diameter of 74.0 cm is brought to rest in 11.0 s. Calculate the magnitude of its angular acceleration in radians/second^2
  42. PHYSICS

    What is the angular momentum of a 2.7 kg uniform cylindrical grinding wheel of radius 12 cm when rotating at 1600 rpm? How much torque is required to stop it in 4.4 s?
  43. physics

    What is the smallest radius of an unbanked (flat) track around which a bicyclist can travel if her speed is 31 km/h and the coefficient of static friction between the tires and the road is 0.29?
  44. 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?
  45. Physics

    Calculate the components parallel and perpendicular to the plane of 150N gravitational force acting on an object on a slope at 20 degrees to the horizontal ?
  46. physics

    An old-fashioned single-play vinyl record rotates on a turntable at 46.0 rpm. What are (a) the angular velocity in rad/s and (b) the period of the motion?
  47. Physics

    A 21.0 kg child descends a slide 3.4 m high and reaches the bottom with a speed of 2.0 m/s. How much thermal energy due to friction was generated in this process?
  48. 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?
  49. 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?
  50. 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
  51. Physics

    Ahmad throws a ball straight up. For which situation is the vertical velocity zero? [Note: Neglect the air resistance] Answer at the top on the way up none of the above on the way down
  52. 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?)
  53. 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?
  54. 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.
  55. Physics

    Calculate the force exerted on a rocket, given that the propelling gases are expelled at a rate of 1800 kg/s with a speed of 3.8×104 m/s (at the moment of takeoff).
  56. Physics

    How does the cochlea sense sound? •Snail shaped tube lined with receptor cells which transmits signals to the brain. Correct?
  57. 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?
  58. 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
  59. 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.
  60. Physics

    A roller-coaster car is moving at 20.0 m/s along a straight horizontal track. What is its speed after climbing a 15.0 m hill? Neglect the effects of friction.
  61. Physics

    If it takes 5 seconds for the baseball to fall, how far from the tower will it land? I used vertical distance formula dy=1/2(g)t^2 and got 122.5 but its one of the answers in the multiple choice. Please help.
  62. physics

    Frosty the Snowman was a jolly happy soul of mass 85 kg. If his initial temperature was -19C , how much heat did he absorb till he was at 25C ?
  63. Physics

    A rocket moves upward, starting from rest with an acceleration of 34.4 m/s2 for 4.40 s. It runs out of fuel at the end of the 4.40 s but does not stop. How high does it rise above the ground?
  64. 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 ?
  65. Physics

    Determine lamda m Oments wavelength of the peak of the Planck distribution annd the corresponding frequency f at these temperature a) 3.00k. b)300k c)3000k
  66. 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?
  67. physics

    A circular swimming pool has a flat bottom and a 4.39 m diameter. It is filled with water to a depth of 1.51 m. There is 1.36 atm of pressure on the top surface.
  68. physics

    The radius of a merry-go-round is 7 meters, and it takes 12 seconds to make a complete revolution. What is the speed of an atom on the outer rim?
  69. Physics

    I need to explain and demonstrate mathematically why it is easier to pull a wheelbarrow than it is to push it. Also, what effect does the component of force parallel to a bicycle crank have?
  70. physics

    a long jumper takes off at an angle of 20 degrees with the horizontal and reaches a maximum height of 0.55 meters at mid- flight. how far did she jump?
  71. Physics

    Your electric jug element produces 1.5kW of power. What is the minimum time it will take to heat 1.5L of water from 20 degrees Celcius to boiling
  72. 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?
  73. 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?
  74. Physics

    I need to explain and demonstrate mathematically why it is easier to pull a wheelbarrow than it is to push it. Also, what effect does the component of force parallel to a bicycle crank have?
  75. Physics

    Steve can paddle his canoe at 10 km/h in still water. If he paddles directly against a river’s current that is moving at 3 km/h, what is Sam’s velocity relative to the shoreline?
  76. Physics

    In the following diagram there is a coefficient of friction, μ, of 0.15 between the 5.0 kg mass and the surface. Calculate the tension in the cable connecting the two masses and the resulting acceleration.
  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

    a point mass of 12.5 kg is hung from an 18.3 m long rope and swings back and forth with an amplitude of 2.34m. what is the oscillation period for the pendulum system?
  79. College Physics

    Construct & solve a problem involving a person swimming across a river which has a waterfall some distance downstream. Please help, I have no idea where to start.
  80. 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.
  81. Physics

    When tossed upward and hit horizontally by a batter, a 0.23 kg softball receives an impulse of 2.0 N·s. With what horizontal speed does the ball move away from the bat?
  82. Physics

    Need help with a question! I worked out A (assuming its right) which leads to B. A) C=1.03x10^-4 uF, A=2.5mm^2, d=0.75um B) If the voltage across the membrane is delta V= 75mV, what is the charge +_Q on each surface A? thanks!
  83. 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?
  84. 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
  85. 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)?
  86. physics

    Qualitatively explain how you would expect the potential energy to change as a glider slides down an inclined air track, where friction is negligible.
  87. physics

    if you wished to warm 100 kg of water by 15 degrees celsius for your bath, how much heat would be required? (give your answer in calories and joules)
  88. Physics 1

    What is the minimum speed a 3,200 pound car can have on a flat road when going around a curve with a radius of 300ft. Take the static coefficient of friction to be 0.8.
  89. 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.
  90. 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?
  91. Physics: Fluids

    A sample of an unknown material weighs 260 N in air and 175 N when immersed in alcohol of specific gravity 0.700.
  92. physics

    A football player is running at a speed of 9m/s hits the goalpost and comes to a stop in 0.050 sec. Calculate his acceleration and compare it with that of gravity.
  93. 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?
  94. 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
  95. physics

    An outfielder throws a 0.150-kg baseball at a speed of 50.0 m/s and an initial angle of 30.0°. What is the kinetic energy of the ball at the highest point of its motion?
  96. Physics

    A train moving with constant speed of 54kmph moves eastwards for 30min then north for 40min find avg velocity
  97. physics

    An 8 hour exposure to a sound level of 95.0 dB may cause hearing damage. What energy in joules falls on a 0.850 cm diameter eardrum so exposed?
  98. 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?
  99. physics

    Find the approximate gravitational red shift in 500 nm light emitted by a compact star whose mass is that of sun but whose radius is 10 km.
  100. PHYSICS

    3 PARTICLES OF MASS 1KG,2KG,3KG PLACED AT CORNER A,B,C OF AN EQUILARERA TRIANGLE A,B AND C.LOCATE THE POSITION OF PARTICLE/FIND COORDINATES