1. physics

    A thermal neutron beam of intensity 1 to the power 11, neutrons/sec is directed for 2 days into a cavity in a block of cobalt initially composed entirely of the stable isotope Cobalt 59. The neutrons are all captured, producing cobalt 60 nuclei which are
  2. Math

    Beth is waiting for her friends plane to land. the plane will land at time T uniformly distributed in 70 minuetes. Determine the probability that the Plane will land in 30 minutes?
  3. physics

    a box of mass 10kg is at rest on a horizontal plane.a force of 20N is applied to it at 30 degrees to the plane.assuming there no frictional force between the box and the plane,calculate the acceleration of the box.
  4. science

    Words to use: Accelerate - Sliding - Brake - Friction - Slipping - Inertia Velocity - Wheel - Strength - Static - Terminal velocity Questions 1. An object will ____?____ when the net force is not zero. 2. ____?____ will never speed up an object. 3. The
  5. physics

    A 3 N weight slides down a ramp made of sandpaper. The coefficient of friction is 0.8, and the ramp is at an angle of 50° to the horizontal. How could you calculate the magnitude of the friction force? A. 3 N × sin(50°) B. 3 N × 0.8 × 50° C. 3 N ×
  6. Physics

    the energy of a ball rolling up an inclined place plane is?
  7. Physics

    how does the MA and the IMA of the inclined plane vary with the inclination angle?
  8. Physics

    how does the MA and the IMA of the inclined plane vary with the inclination angle?
  9. spring- physics

    A 2.0-kg box rests on a plank that is inclined at an angle of 65 degrees above the horizontal. The upper end of the box is attached to a spring with a force constant of 400 N/m. If the coefficient of static friction between the box and the plank is 0.22,
  10. Spring Physics

    A 2.0 kg box rests on a plank that is inclined at an angle of 65° above the horizontal. The upper end of the box is attached to a spring with a force constant of 19 N/m, as shown in Figure 6-32. If the coefficient of static friction between the box and
  11. Math

    Here is the question: The mortgage department of the company is selling two model homes that are located on the same block. The square footage, as well as the type of model, determines the cost of these homes. e) The second home has 1000 square feet less
  12. Physics

    A toy plane of mass 0.624 kg is flown in a circle when attached to a string. The plane moves around the circle with a rotational speed of 8.09 rpm. The length of the string is 2.60 m. What is the tangential velocity, v, of the plane? .
  13. Physics

    A toy plane of mass 0.624 kg is flown in a circle when attached to a string. The plane moves around the circle with a rotational speed of 8.09 rpm. The length of the string is 2.60 m. What is the tangential velocity, v, of the plane? .
  14. physics

    A daredevil plans to bungee jump from a balloon 53.0 m above a carnival midway. He will use a uniform elastic cord, tied to a harness around his body, to stop his fall at a point 10.0 m above the ground. Model his body as a particle and the cord as having
  15. physics

    A 14.7 kg crate is pulled up a rough incline with an initial speed of 1.5 m/s. The pulling force is 124.0 N parallel to the incline, which makes an angle of 11.0 ◦ with the horizontal. The coefficient of kinetic friction is 0.31 and the crate is
  16. physics

    a projectile is launched outward at an angle theta above an incline plane elevated an angle alpha above the horizon. when the projectile hits the plane it is moving horizontally. prove for this case that the angle theta must satisfy the following
  17. physics

    A child, starting from rest at the top of a playground slide, reaches a speed of 7.0 meters per second at the bottom of the slide. What is the vertical height of the slide? [Neglect friction.]
  18. Physics

    A cylindrical 7.00-kg reel with a radius of 0.60 m and a frictionless axle, starts from rest and speeds up uniformly as a 3.00-kg bucket falls into a well, making a light rope unwind from the reel (Fig. P8.36). The bucket starts from rest and falls for
  19. Math

    The ages in years of the houses on Kelly’s block are 20, 26, 11, 2, 28, 18, 2, and 27. Find the mean age of the houses. Find the median age. Find the mode. Which measure(s) would you use to represent the ages of the houses? Explain
  20. dynamics

    a mass m= 10kg is hanging from the end of a spring. intially the spring is unstretched when the mass is pushed perfectly downward with an initial velocity of 1 m/s. the spring constant is k=400n/m and the acceleration of gravity is g=9.81m/s^2. find the
  21. physics

    A car weighing 1.0 x 10^4N is parked on a 34 degree slope. The brakes fail and the car starts to slide down the hill. Assume no friction. Show your work, and determine a) the acceleration of the car, and b) after it has moved 28.0 m, how fast is it moving?
  22. physics

    a skier is acceleration down a 30.0 degree hill at 3.50 m/s^2. how long (in seconds) will it take her to reach the bottom of the hill. assuming she starts from rest and accelerates uniformly, if the elevation change is 120m?
  23. 5 Pre-Calculus Questions

    1. What is the value of x in the right triangle below? If needed, round your answer to two decimal places. 32 angle, 15 inches, find the x in base… 2. A 10-foot ladder is leaning up against the side of a building so that the top of the ladder reaches the
  24. physics

    A truck starts from the rest and moves with a accelaration 1.5m/s^2 ,at the same time a car which is 150m behind the truck starts from the rest with an accelaration of 2m/sec^2. Find the time which the car will overtake the truck and the distance travel.
  25. physics

    A 31.0 kg object slides down a slope which is inclined at an angle of 20.0o to the horizontal. What is the normal force exerted by the slope?
  26. Physics

    Calculate how much work does a block of aluminum of mass 100 kg do if it is heated at P = 1 atm from 20 degrees to 660 degrees. n.b. - The density of solid aluminum at 20 degrees is p= 2.7 g/cm^3. When it is liquid at 660^C the density of the liquid state
  27. Physics

    Some forms of cancer can be treated using proton therapy in which proton beams are accelerated to high energies, then directed to collide into a tumor, killing the malignant cells. Suppose a proton accelerator is 4.21 m long and must accelerate protons
  28. Physics

    Some forms of cancer can be treated using proton therapy in which proton beams are accelerated to high energies, then directed to collide into a tumor, killing the malignant cells. Suppose a proton accelerator is 4.21 m long and must accelerate protons
  29. calculus

    A 160-lb man carries a 25-lb can of paint up a helical staircase that encircles a silo witha radius of 20 ft. If the silo is 90 ft high and the man makes exactly three complete revolutions, how much work is done by the man against gravity in climbing to
  30. Physics

    A bead slides without friction around a loop–the–loop (see figure below). The bead is released from rest at a height h = 3.60R. (a) What is its speed at point ? (Use the following as necessary: the acceleration due to gravity g, and R.) v = So I can't
  31. Physics

    A bead slides without friction around a loop–the–loop (see figure below). The bead is released from rest at a height h = 3.60R. (a) What is its speed at point ? (Use the following as necessary: the acceleration due to gravity g, and R.) v = So I can't
  32. physics

    a bullet of mass 20g is fired into a block of wood of mass 400g . if the bullut and wood move together with speed of 20ms-1 calclate(i) speed with the bullet hits the wood ii the kinetic energy lost iii state the energy changes involed
  33. physics

    Only two forces act on an object (mass = 4.20 kg), as in the drawing. (F = 73.0 N.) Find the magnitude and direction (relative to the x axis) of the acceleration of the object. magnitude m/s2 direction ° counterclockwise from the +x axis The angle from
  34. science

    A body of mass m=2.6 kg is standing on a ramp inclined in an angle of α=14.9 degrees. The static friction coefficient between the ramp and the body is μ=0.29. The ramp, which is inclined to the left, is in a train, which accelerates to the right.
  35. science

    A body of mass m=2.6 kg is standing on a ramp inclined in an angle of α=14.9 degrees. The static friction coefficient between the ramp and the body is μ=0.29. The ramp, which is inclined to the left, is in a train, which accelerates to the right.
  36. math

    there are 5,280 feet in a mile.if a air plane is flying at 35,000 feet above sea level how high is it a.7 miles high b.a little less than 7 miles high c. a little more than 7 miles high
  37. English

    Question 6 Which sentence contains a shift in person? He couldn't refuse when offered another helping of dessert; sometimes you just can't resist! The lake contained garbage that flows through the storm drains. If a student does not understand the
  38. physics

    I am struggling with this. A wombat of mass 22.0 kg starting at rest slides 13.0 m down a tree at a speed of 5.80 m/s just before reaching the bottom. (a) What is the change in the gravitational potential energy of the wombat during the trip? (b) What is
  39. physics

    A bartender slides a glass mug with a mass of 520 g along the top of a level bar. The coefficient of kinetic friction between the glass and the bar is 0.09. When the glass leaves the bartender's hand, it is moving, it is moving at a speed of 3.9 m/s. How
  40. physic

    A force paralled to an inclined plane is used to raise a load of 500N through a height of 3M While the load moves a distance of 30M along the plane (a) How much work is done on the load ? (b)if the efficency is 80% calculate the effort (c)how much work is
  41. Chemistry

    Hydrogen is burned in oxygen to release heat. How many grams of hydrogen gas must be burned to release enough heat to warm a 50.0 g block of iron, giving 5 mol of water? 2 H2(g) + O2(g) → 2 H2O(g) ΔH = −484 kJ Iron has a specific heat of
  42. physics 111

    A block of mass 2.50 kg is pushed 2.80 m along a frictionless horizontal table by a constant 10.0 N force directed 25.0° below the horizontal. 1) what's the work done by the applied force? in joules 2)whats the work done by the normal force exerted by the
  43. Laws of Physics

    A block and tackle has a velocity of 6 and it is being used to raise a mass of 68 newtons through 3 meters. The efficiency is 60% Calculate the amount of energy needed to lift the mass through 3 meters and calculate the amount of energy that was put into
  44. math

    a farmer plants a square block of trees. he plants another 25 tress and still has a square plantation. how many trees in the new plantation
  45. English

    1. You must blow up buildings one street away from the fire. 2. You must blow up buildings one blodk away from the fire. ========== Does #1 mean #2? Does 'street' mean 'block' in the sentence?
  46. Physics

    A rope of mass m uniformly distributed along it's length l can slide without friction on a horizontal table. At instant t=0 the hanging part of the rope has a length b, and the rope is held at rest. When it is left, the rope begins to slide. At instant t
  47. physics

    A 2.606 kg block is on a horizontal surface with ìk = 0.160, and is in contact with a lightweight spring with a spring constant of 577 N/m which is compressed. Upon release, the spring does 7.212E-1 J of work while returning to its equilibrium position. I
  48. physics

    A 0.9 kg hollow ball with a radius of 0.12 m, filled with air, is released from rest at the bottom of a 2.0 m deep pool of water. How high above the water does the ball shoot upward? Neglect all frictional effects, and neglect the ball's motion when it is
  49. Physics

    A crate of mass 0.812 kg is placed on a rough incline of angle 35.3 degrees. Near the base of the incline is a spring of spring constant 1140 N/m. The mass is pressed against the spring a distance x and released. It moves up the slope 0.154 meters from the
  50. Physics

    A crate of mass 0.812 kg is placed on a rough incline of angle 35.3 degrees. Near the base of the incline is a spring of spring constant 1140 N/m. The mass is pressed against the spring a distance x and released. It moves up the slope 0.154 meters from the
  51. physics

    A test rocket is launched by accelerating it along a 200.0-{\rm m} incline at 2.24{\rm m/s^2} starting from rest at point A (the figure (Figure 1) .) The incline rises at 35.0 ^\circ above the horizontal, and at the instant the rocket leaves it, its
  52. Physics

    A car starts from rest accelerate uniformly until it reaches a velocity of 30m/s after 5s.it traves with uniform velocity for 15s and is being brought to rest in 10 with a uniform retardation.dEtermine the following (a) the acceleration of the car.(b) the
  53. Physics

    A daredevil attempts to swing from the roof of a 24m high bulding to the bottom of an identical building using a 24m rope. He starts from rest with the rope horizontal, but the rope will break if the tension force in it is twice the weight of the
  54. Physics

    A lumberjack (mass = 104 kg) is standing at rest on one end of a floating log (mass = 234 kg) that is also at rest. The lumberjack runs to the other end of the log, attaining a velocity of +3.18 m/s relative to the shore, and then hops onto an identical
  55. Philosophy

    If Plato had to write a letter to Aristotle about his philisophical viewpoints concerning his philosophies, what do you think he would write about? I need some help with one of my papers. Need ideas, opinions anything. I am having a writers block. Check
  56. english(check answers)

    please check answers 7.which of these sentences shows correct comma usage? A.Yes i enjoy writing poetry in my spare time.(I PICK THIS) B.After,a while,i suppose,the boy became less scared of the new girl. C.By the end of the first stanza,i had guessed that
  57. Physics

    A batted baseball is hit with a velocity of 47.3 m/s, starting from an initial height of 8 m. Find how high the ball travels in two cases: (a) a ball hit directly upward and (b) a ball hit at an angle of 70° with respect to the horizontal. Also find how
  58. true

    A mango fruit drops to the group from the top of it's tree which is 5m high. How long does it take to reach the ground. Note G Is equal to 10m-2
  59. PHYSICS PLEASE HELP BILLY!!! there are about thr

    A 10.2 kg crate is pulled up a rough incline with an initial speed of 1.5 m/s. The pulling force is 123.0 N parallel to the incline, which makes an angle of 14.6◦ with the horizontal. The coecient of kinetic friction is 0.39 and the crate is pulled
  60. physics

    A child and sled with a combined mass of 58.9 kg slide down a frictionless hill that is 8.09 m high at an angle of 23◦ from horizontal. The acceleration of gravity is 9.81 m/s2 . If the sled starts from rest, what is its speed at the bottom of the
  61. physics

    a force of 200 N is exerted at an angle 30 degrees with respect to the horizontal on an object whose mass is 30kg. the coefficient of friction between the object and the surface is the 0.2.(a)what is the frictional force?(B) what is the acceleration of the
  62. math

    In the given diagram,AB represents a vertical pole and CD represents a 40 m high tower both of which are standing on the same horizontal plane.From the top of the tower,the angles of depression of the top and the foot of the pole are 24 degrees,30 inches
  63. Physics

    A pendulum 1.70m long is released (from rest) at an angle 30 degrees. 1. Determine the speed(m/s) of the 60.0g bob at Theta = 15. 2. Determine the tension in the cord at the lowest point Theta = 0. 3. Determine the tension in the cord at Theta = 15. A
  64. physics

    2. What value did you calculate for the index of refraction of the glass block in Part 2? How does your value compare to the accepted value of 1.53? Calculate the percentage error. Different materials have distinct indexes of refraction. Explain how you
  65. Writing

    Please grade this and make corrections. ACT writing prompt: The Children's Internet Protection ACT (CIPA) requires all school libraries receiving certain federal funds to install and use blocking software to prevent students from viewing material
  66. PHYSICS

    3. A particle of mass m= 5.00 kg is released from point A(at rest) and slides on the frictionless track shown in Figure below. Determine: ( 8 marks ) a. the particle’s speed at points B and C and (4marks) b. the net work done by the gravitational
  67. Chemistry

    using kinetics explain: a.the increasing of concentration of reactants increases the rate of reaction. b.the addition of a catalyst increases the rate at which a reaction will take place. c.and increase in temperature increases reaction rate. d.a catalyst
  68. Physics

    A thin uniform rod has mass M = 0.5 kg and length L= 0.49 m. It has a pivot at one end and is at rest on a compressed spring as shown in (A). The rod is released from an angle θ1= 55.0o, and moves through its horizontal position at (B) and up to (C)
  69. Physics

    This is a theoretical question, ignore the numbers. A 205-kg log is pulled up and to the right on a ramp by means of a rope that is parallel to the surface of the ramp. The ramp is inclined at 30.0 degrees with respect to the horizontal. The coefficient of
  70. pre algebra

    Which polynomial does the model represent? and then it has one big black block, 2 thin white blocks, 3 thin black blocks, 3 single white cubes, and one single black cube. Please help ASAP!!!
  71. Physical Science

    A block of iron is transported to the moon . Which of the following is true 1) Both its mass and weight remain unchanged. 2)Its mass remains the same, but its weight decreases 3)both its mass and weight decreases 4)Its mass decreses, but it weights remain
  72. physics

    A .22 rifle bullet traveling at 360m/s strikes a block of wood, which penetrates to a depth of .110m. The mass of the bullet is 1.80g. Assume a constant retarding force.A) how much time is required for the bullet to stop? b) what force in newtons soes the
  73. Physics

    I have learnt that when we push an object on a horizontal plane with a certain angle, we are increasing its normal reaction and therefore friction increases. Whereas if we pull it, friction decreases. Is that true? Yes, there is more friction if you push
  74. Geometry ( helllppp pleaaassse )

    A point on the ceiling of a room is 12ft. from each of the vertices of a triangle on the floor whose legs are 6ft. A and 8ft. respectively. find the length of the ceiling. 2. With a 12ft. pole marked in feet, how can one determine the foot of the
  75. PHYSICS (what is a dynamic equation????)

    A car of mass Mc is connected to mass m2 by a string. The string passes over a solid cylindrical pulley, which has a frictionless bearing, of radius R and mass M. when the system is released from rest the string doesn't slip, the car moves down the
  76. Microtomy

    I need to infiltrate a sample block of wood for sectioning on a microtome. The formula for the infiltrating media is 70% Ethylene Glycol 1500 and 30% Lauric acid. Both components are in a powder form. The instructions don't indicate whether this is
  77. accounting

    Tyler Constructions constructed a new campus block to house Business School. The building cost a tool of $180,000,000 to construct and was completed 30 March 2011, with an expected useful life of 60 years and residual value of $10,000,000. The building is
  78. As Physics

    Motion and Projectiles Homework-Due tommorow Extended Writing Task: Freefall Two identical steel balls are released from rest above cylinders containing oil as shown in the diagram below.The balls travel vertically until they reach the bottom of the
  79. Math

    Fay's rubber ball bounces exactly half the height from which it is dropped. She drops the ball from the top of a building that is 64 meters tall. How high will the ball bounce on its eighth bounce. Could someone explain this? Thank you! Natalie 1/2 of 64=
  80. math

    A maker of cubic number blocks packs a rectangular box so that there are 11 blocks along one edge, 8 blocks along the second edge and 2 blocks along the third edge. How many blocks will be shipped in this box. If each block has a side of 4cm, what is the
  81. Physics

    Some forms of cancer can be treated using proton therapy in which proton beams are accelerated to high energies, then directed to collide into a tumor, killing the malignant cells. Suppose a proton accelerator is 4.0 m long and must accelerate protons from
  82. physics

    Some forms of cancer can be treated using proton therapy in which proton beams are accelerated to high energies, then directed to collide into a tumor, killing the malignant cells. Suppose a proton accelerator is 4.21 m long and must accelerate protons
  83. Early Child Ed.

    Will you check to see if I have chosen the most appropriate choice to this question? Which would be the best way to welcome a child into the classroom in the morning when his mother drops him off? A. "Good morning,Joshua. We have new crayons to use later
  84. physics

    Two identical thin wires are oriented along the x and y axes. With current on x plane going North. Current on y plane going West.Both carry the same current I, and there is no electrical contact between the wires. The points A, B, C, D are each equidistant
  85. physics

    A skier is accelerating down a 30.0° hill at a = 4.10 m/s2 a) What is the vertical component of her acceleration? b) How long will it take her to reach the bottom of the hill, assuming she starts from rest and accelerates uniformly, if the elevation
  86. Physics

    forty 2.0 kg blocks 20.0 cm thick are used to make a retaining wall in a backyard. Each row of the wall will contain 10 blocks. you may assume that the first block is the reference level. How much gravitational potential energy is stored in the wall when
  87. physics

    A trolley while going down an inclined plane has an acceleration of 2 cm/s2.What will be the velocity 3 secs after its start?
  88. College Physics

    In a proton linear accelerator, a 8.6 proton current hits a target. 5.4×10^16 protons/second hit the target. How much energy is delivered to the target each second if each proton has a kinetic energy of 26 MeV and loses all its energy in the target? U =
  89. Math

    Determine the equation of the graph in the form y = acos(bx). I will try and describe the Graph. -It starts at the origin (0,0) -It has a minimum value of -2 -It has a maximum value of 2. -It has an x-intercept of 90 degrees. -It starts moving downward
  90. Math

    Determine the equation of the graph in the form y = acos(bx). I will try and describe the Graph. -It starts at the origin (0,0) -It has a minimum value of -2 -It has a maximum value of 2. -It has an x-intercept of 90 degrees. -It starts moving downward
  91. ALGEBRA 2

    A plane takes off from an aiport and flies east at a speed of 350 mi/h. Ten minutes later, a second plane takes off from the same airport and flies east at a higher altitude at a speed of 400 mi/h. How long does it take the second plane to overtake the
  92. 7th grade math help Ms. Sue please

    Hi! Sorry to keep bothering you with questions. Can you help me on 6 and 13 please? I cannot find the answers. Also, can you check my answers to 11 and 19? Thanks! 6. If point A is located at (0, –8) and B is located at (4,–5), what is the distance
  93. Physics

    A ray of light which is incident in air on the surface of the glass block is deviated through 15 degree. The angle of incidwnce in air is 60 degree.What is the angle of refraction in glass?Also calculate the critical angle for glass air interface.
  94. Physics

    A bowling ball of mass M and radius R is thrown along a level surface so that initially ( t= 0) it slides with a linear speed but does not rotate, see the figure. As it slides, it begins to spin, and eventually rolls without slipping. How far has the ball
  95. Physics

    A bowling ball of mass M and radius R is thrown along a level surface so that initially ( t= 0) it slides with a linear speed but does not rotate, see the figure. As it slides, it begins to spin, and eventually rolls without slipping. How far has the ball
  96. math

    on a scale drawing, the length of a plane is 45 cm. The actual length of the plane is 90 m. What is the scale used?
  97. physics

    A car is parked on a cliff overlooking the ocean on an incline that makes an angle of 19.0° below the horizontal. The negligent driver leaves the car in neutral, and the emergency brakes are defective. The car rolls from rest down the incline with a
  98. troy

    A car is parked on a cliff overlooking the ocean on an incline that makes an angle of 15.0° below the horizontal. The negligent driver leaves the car in neutral, and the emergency brakes are defective. The car rolls from rest down the incline with a
  99. physics

    A car is parked on a cliff overlooking the ocean on an incline that makes an angle of 19.0° below the horizontal. The negligent driver leaves the car in neutral, and the emergency brakes are defective. The car rolls from rest down the incline with a
  100. Physics

    I keep on getting the wrong answer I don't know if there is even static friciton in this problem in the begining before the rope snaps or not and if so if it must be equal to the Mu they give because there is only one but you can't have the same values for