# physics please HELP !

74,672 results, page 88

1. ### PHYSICS

COULD YOU FURTHER EXPLAIN HOW MANY BTU ARE REQUIRED TO RAISE THE TEMP OF500 GALLONS OF WATER FROM 70 DEGRESS TO 160 DEGREES FAHRENHIET
2. ### Physics

Given an angle of 30 degrees, find the minimum initial speed of a cannon ball that travels in a horizontal distance of 15000 mi.
3. ### physics

what will be the centipetal acceleration on a man whose mass is 80 kg,when resting on a ground at the equator if the radius of the earth'R' is 6.4x10 power 6 meter.
4. ### Physics

How much work did the movers do (horizontally) pushing a 140-kg crate 10.1 m across a rough floor without acceleration, if the effective coefficient of friction was 0.60?
5. ### Physics

There is a flash of lighting that gives out a 25 C of negative charge from cloud to ground. Determine the amount of electrons involved? Do i use the formula F=qE I know one coulomb is 1.6 * 10 ^-19
6. ### Physics

In the rope climb, a 68 kg athlete climbs a vertical distance of 9.0 m in 13 s. What minimum power output was used to accomplish this feat? In Watts
7. ### physics

A block of wood is 8.00cm long, 20.0cm high, and 0.10m wide. its mass is 1.00kg. what is its density in g/cm3?
8. ### Physics

How is it that an electron accelerates towards the protons (nucleus) in a hydrogen atom? I had thought that the electric forces acting on each other is equal so they are in equilibrium.
9. ### college physics

How many revolutions per minute would a 18 m-diameter Ferris wheel need to make for the passengers to feel "weightless" at the topmost point?
10. ### Physics

A roller coaster moves 4.2 m horizontally, then travels 6.9 m at an angle of 30º above the horizontal. What is the resultant displacement from its starting point?
11. ### Physics

A weightlifter raises a barbell of mass 150 kg from the floor to over his head 2.5 meters in 3 seconds. What is his average power input?
12. ### Physics

Three identical charges of 2.0 uC are placed at the vertices of an equilateral triangle, 0.15m on a side. Find the net force acting on each angle.
13. ### physics

Given. a = 25.1 cm and b = 51.2 cm and the forces are F1 = 10.3 N, F2 = 10.6 N and F3 = 14.7 N. The angle between F2 and the horizontal is θ = 27.9 °. Find the magnitude of the net torque on the wheel about the axle through O. Answer in units of N m.
14. ### Physics

Starting from rest, a skier slides 100 m down a 28 degree slope.How much longer does the run take if the coefficient of kinetic friction is 0.17 instead of 0?
15. ### physics

how the frequency of the sound produced will change in the case of aluminium sting of length 15cm when the string is tied between two ends
16. ### physics

Explain why it would not make sense to use a full-size glass thermometer to measure the temperature of a thimbleful of hot water?
17. ### physics

Calculate the magnitude of the electric field at one corner of a square 1.48m on a side if the other three corners are occupied by 1.92×10−6 Ccharges.
18. ### physics PLEASE HELP!

The pilot of an airplane traveling 250km/h wants to drop supplies to flood victims isolated on a patch of land 190m below.
19. ### physics

Calculate the work required to lift a 20kg object from the floor to a height of 2 meters. Give your answer in Joules
20. ### Physics

Calculate the electric field at a point 3.12 cm perpendicular to the midpoint of a 2.23 m long thin wire carrying a total charge of 5.45 uC.
21. ### Physics

If you ask a friend to drive a small nail into a piece of wood placed on top of a pile of books on your head. Why doesn't this hurt you?
22. ### PHYSICS

How much work did the movers do (horizontally) pushing a 140-kg crate 10.1 m across a rough floor without acceleration, if the effective coefficient of friction was 0.60?
23. ### physics

Two wires run parallel to each other with currents I1 = -60.3 A, and I2 = 44.1 A. If they are a = 0.12 m apart, what is the magnitude of the force (N) per meter of length? I used the formula (f/L)=Uo(I1)(I2)/(2(pi)(r)) I got 4.43810^-2(N/m)but it was wrong..I'm not sure what ...
24. ### Physics

How is it that an electron accelerates towards the protons (nucleus) in a hydrogen atom? I had thought that the electric forces acting on each other is equal so they are in equilibrium.
25. ### Physics

A car that was initially at rest reaches a final speed of +50.0 m/s over a displacement of +55.0 m. What is the magnitude of the acceleration? Find the time it took to travel the first 55 m.
26. ### Physics

If a disk and hoop are released simutaneously 1.0m above the ground at a 30 degree incline which one will reach the bottom faster? Show mathematically.
27. ### PHYSICS

IF EARTH WERE TO ROTATE FASTER THAN ITS PRESENT SPEED THEN WEIGHT PF OBJECT WILL DECREASE AT EQUATOR BUT REMAIN UNCHANGED AT POLES why?
28. ### physics

a stone dropped from the top of a cliff received ground in 4 second and burries itself at 0.8 meter into mud.calculate height and retardation.
29. ### Physics

Two pans of a balance are 50cm apart. If the fulcrum is displaced by 1cm what percentage is the true weight marked up? the answer i got was 1.3%, please help if wrong (which it probably is).
30. ### Maths/Physics

Is it possible to share a four fingered Kit Kat equally between 5 people if you can only break any one piece in half? Prove whether it is possible or impossible.
31. ### physics

A car starts from rest and accelerates uniformly to a velocity of 8ft/s after traveling 250 ft. Find its acceleretaion. Help me with this pleeaase. Thank you.
32. ### physics

While rearranging a dorm room, a student does 307 J of work in moving a desk 1.1 m. What was the magnitude of the applied horizontal force?
33. ### Physics

what is the equation describing the motion of mass on the end of a spring which is streached 8.8 cm from equlibrium and then released from rest and whose period is .66 s ? what will be its displacement after 1.8 s
34. ### physics

Two loudspeakers are 2.54 m apart. A person stands 3.04 m from one speaker and 3.50 m from the other. What is the lowest frequency at which destructive interference (sound cancellation) will occur at this point?
35. ### physics

If a professional jumper jumps in a running trainn and remains in air (say,4 ~5 sec),does he returns back his original position?
36. ### Physics

A point light source is kept in front of a convex mirror at a distance of 40cm.find the position of image by drawing
37. ### Physics

Two uncharged metal spheres, spaced 20.0 cm apart, have a capacitance of 28.0 pF. How much work would it take to move 14.0 nC of charge from one sphere to the other? *Please report answer in Joules.
38. ### Physics

A = 145 rock is hoisted upward with an acceleration of 1.46 by a vertical chain of negligible weight. What is the free body diagram?
39. ### physics

A 4.5 kg object is accelerated from rest to a speed of 39.2 m/s in 76 s. What average force was exerted on the ob- ject during this period of acceleration? Answer in units of N
40. ### physics

Two particles with Q1 = 40 µC and Q2 = 87 µC are initially separated by a distance of 2.6 m and then brought closer together so that the final separation is 1.7 m. What is the change in the electric potential energy?
41. ### Physics

An object is dropped from a platform 100 feet high. Ignoring wind resistance, what will its speed be when it reaches the ground?
42. ### Physics

1. A 2,000 kilogram truck traveling at 60km/h strikes a tree and stops in 0.75 seconds. How large is the force that causes this to occur?
43. ### AP Physics

A ball has an initial velocity of 3 m/s. If there is no friction, what is the highest it could roll? What would the qualitative bar graphs and energy flow diagram look like?
44. ### physics

An aeroplane taking off from a field has a run of 500 meters. What is the acceleration and take off velocity if it leaves the ground 10 seconds after the start ?
45. ### Physics

A crane lifts a Load of 50000g very slowly through a distance of 150cm vertically, calculate the work done against gravity if g=10.mls2
46. ### AP physics

Two locomotives approach each other on parallel tracks. Each has and average spend of 150 km/h with respect to the ground. If they are initialy 8.5 km apart, how Long will it be before they reach each other?
47. ### Physics

A man was lost in the woods. He wanders 3 km north, then 7 km east, then 7 km south, then 4 km west. What is the magnitude and direction of his resultant displacement?
48. ### physics

suppose a car travels at a constant 10m/s how far would it move in 1hr? in 1min? 1ms? could you please explain how i would solve this equation
49. ### physics

A car traveling at 91.0 km/h approaches the turnoff for a restaurant 30.0 m ahead. If the driver slams on the brakes with an acceleration of -6.40 m/s^2, what will her stopping distance be?
50. ### Physics

A weightlifter raises a 200 kg barbell over his head from the floor a displacement of 2m in 2.2 seconds. What is the average power he develops during the lift?
51. ### physics

A piano tuner hears one beat every 2.8 s when trying to adjust two strings, one of which is sounding 440 Hz, so that they sound the same tone. How far off in frequency is the other string?
52. ### physics

1 A steel wire, 150 m long at 10¢XC, has a coefficient of linear expansion of 11 „e 10ƒ{6/C¢X. Give its change in length as the temperature changes from 10„aC to 45„aC. 5.8 cm
53. ### physics

How much work did the movers do (horizontally) pushing a 180- crate 10.6 across a rough floor without acceleration, if the effective coefficient of friction was 0.50?
54. ### physics

An electric iron has a resistance of ohms. How much heat energy is produced in 10 minutes if the current passing through the device is 10 amps?
55. ### Physics

A wire length 2m and radius 1mm is stretched by 25mm on application of a force of 1000N.Calculate the young modulus
56. ### Physics

A 1200 N force is exerted on a 700 kg crate to move it across a loading dock. If the coefficient of friction is .50 what is the crates acceleration?
57. ### physics

a baseball is released at rest from the top of a building.it hits the ground after falling for 6seconds . what was the height from which the ball was dropped
58. ### Physics

A block weighing 6.2 N requires a force of 2.2 N to push it along at constant velocity. What is the cooefficient of friction for the surface? Plsssss help asap..
59. ### physics

A satellite orbits at an average altitude of h = 423 km. How long does it need to complete one full orbit? Use REarth = 6370 km and mEarth = 5.98 x 10^24 kg
60. ### physics help

A flywheel turns through 32 rev as it slows from an angular speed of 2.1 rad/s to a stop. How much time is required for it to complete the first 16 of the 32 revolutions?
61. ### physics

Find the pottential energy of a boy of mass 10kg standing on a building floor 10 meters above the ground level p.e?
62. ### Physics

What is the magnitude of the electric field at a point midway between a −8.3μC and a +5.4μC charge 10cm apart? Assume no other charges are nearby.
63. ### physics

In order to clearly read a book 16 cm away, a farsighted girl needs an image to be 36 cm from her eyes. What focal length is needed for the lens in her eyeglasses?
64. ### physics

a d'arsonval meter movement deflects to 0.8mA. what is the peak value of the alternating current if the instrument uses full-wave rectification?
65. ### physics

Question part Points Submissions 1 0/1 1/5 Total 0/1 ...If a truck traveling 38.0 km/h uniformly accelerates up to 55.0 km/h, what's its average speed in the process?
66. ### physics

How strong an electric field is needed to accelerate electrons in a TV tube from rest to one-tenth the speed of light in a distance of 4.9 cm ?
67. ### physics

What's kinetic energy in electron volt of a triply ion iron which has been accelerated from rest through a potential difference of 100v?
68. ### physics

A ball has a diameter of 3.86 cm and average density of 0.0836 g/cm3. What force is required to hold it completely submerged under water?
69. ### Physics

If a tank is standing up i.e 1.200 dia x 1.100 high with 650 kg inside, How much water pressure to lift it Cheers
70. ### Physics

An object is dropped from a cliff thatis 256 m above the sea. just prior to splashing into the water, how fast is it going? How long did it take to fall?
71. ### physics

When a 80kg block of mass is pushed by 400 Newton at an angle of 37 degrees above the horizontal to accelerate from 20 m/s what will be the final velocity after 6 second
72. ### science/physics

just trying to find out what temperature the water in my celcius heating system needs to be to achieve an air tempature of 68 degrees ferinheidt
73. ### physics

a person whos mass is 102 kg stands on a beam supported by two ropes , A and B, he is standing on one foot to help you solve this problem.
74. ### physics

Fruity Florida farmers fecklessly fling flying fountains of water on the fruit during cold snaps. Explain why they do this
75. ### Physics

A racing car has a mass of 1540 kg. What is its kinetic energy if it has a speed of 110 km/h? Assume that air resistance is negligible.
76. ### physics

The position of a particle moving along the x-axis is given by x = (13 + 11t − 1.5t2), where t is in seconds and x is in meters. What is the average velocity during the time interval from t = 1s to t = 4 s?
77. ### physics

what average force is needed to accelerate a 7.00-gram pellet from rest to 125m/s over distance of a .800m along the barrel of a rifle.
78. ### Physics

A wire length 2m and radius 1mm is stretched by 25mm on application of a force of 1000N.Calculate the young modulus
79. ### physics

A 2.0 kg mass is sliding on a flat surface, with an initial speed of 20 m/s, and a coefficient of friction of 0.2. what is the magnitude of its acceleration? I know the answer is 2.0 m/s^2, but can someone show me how ?
80. ### physics

If you drop an object, it will accelerate down- ward at a rate of g = 9.8 m/s2. If you throw it downward instead, its accel- eration (in the absence of air resistance) will be
81. ### Physics

1) Please describe the structure of a hurricane,and how they work. Include a discussion of how energy is transferred from the warm ocean water up to the sky.
82. ### Physics

How much work is done pushing a wheel barrow full of cement 5.3m forward if a force of 500N is applied 20 degrees from the vertical?
83. ### physics

The potential difference applied to an X-ray tube is 5 kV and the current through it is 3.2 mA. Then the number of electrons striking the target per second and speed at which they strike?
84. ### Physics

A motorcycle with a mass of 350 kg is accelerated from rest to a velocity of 30 m/s by a force of 4000 N. calculate the distance over which this acceleration occurred.
85. ### physics

how does mass energy relate to the hydrogen bomb? i can't find anything that simply explains this to me and i need6 it for a powerpoint presentation tomorrow please help.
86. ### Physics

compute for the power while pushing an object by a 200N force making 18 degrees above the horizontal covering a distance of 7.5m in 0.5 minute?
87. ### Physics

Ajuggler throws a ball from height of 0.950 m with an overall velocity of =4.25 m/s, 67 degrees above horizontal and misses it on the way down. What is the overall speed when it hits the ground?
88. ### Physics

Temperature of a diatomic gas is 300k. If the moment of inertia of its molecules is 8.28*10^-38 gm-cm^2. Calculate their root mean square angular velocity.
89. ### physics

TWO LOCOMOTIVES APPROACH EACH OTHER ON PARALLEL TRACKS. EACH HAS A SPEED OF 95KM/H WITH RESPECT TO THE GROUNG. IF THEY ARE INITIALLY 8.5KM APART, HOW LONG WILL IT BE BEFORE THEY REACH EACH OTHER?
90. ### physics

an object weighs 10N on earth .what is the objects weight on a planet one tenth the earths mass and one half its radius?
91. ### physics

A 750 kg rocket accelerates straight upward from the ground at 60 m/s2. What is the force (thrust) provided by the engine? with a gravitational pull of 10 m/s2 down
92. ### Physics

What is the total kinetic energy if a 0.30 kg block is sliding on a smooth horizontal surface at 2.5 m/s, heading towards a light spring that is in equilibrium?
93. ### Physics

Two loudspeakers are 2.42 m apart. A person stands 3.42 m from one speaker and 2.82 m from the other. What is the lowest frequency at which destructive interference (sound cancellation) will occur at this point?
94. ### physics

A certain centrifuge produces a centripetal acceleration of magnitude exactly 1090g at a point 12.3 cm from the axis of rotation. Find the number of revolutions per second.
95. ### Physics(Please help)

Determine the final speed assuming that the time elapsed since t=0 is 2.4s. Initial velocity is +12m/s acceleration is +3.4m/s^2 I tryed doing 12/2.4 and then 12/3.4 but both of these were incorrect? I am not sure what to do. Thank you.
96. ### Physics

How fast (in rpm) must a centrifuge rotate if a particle 69-cm from the axis of rotation is to experience an acceleration of 200438 g's? (can you show me how you get the answer) be thorough
97. ### Physics

Calculate the energy released when 235 U fissions resulting in two lighter stable nuclei with mass numbers 140 and 93.Please help!
98. ### Physics - please, I really need this

Show mathematically that a diverging lens will alway produce an upright image. [i.e. prove that hi is positive if f is negative] I'm not even sure how to start this. Can someone please help me?
99. ### Physics

Why does the blood of deep sea divers look greenish-black in underwater photographs taken with natural light, but red when flashbulbs are used?
100. ### physics

a motorboat travels 25.0 km/h in still water. what will be the magnitude and direction of the velocity of the boat if it is directed upstream on a river that flows at the rate of 4.00 km/h?