# Math/Physics

215,588 results, page 72
1. ## physics PLEASE I NEED HELP

Wally now lift the box of the floor and put it on a shelf. Does he doing any work? If not why? If so .what energy change is accurring?
2. ## physics

A bicycl rider starts from rest and moves with uniform acceration of 1.5m\s^2 it is velocity reachs 7.5m\s of a distance .......

What is the potential difference if a resistance of 25 ohms produce a current of 250 amperes?
4. ## physics

A car with a weight of 5000.0 N is accelerated across a level surface at 2.5 m/s^2. What is the net force acts on the wagon? (g= 9.81 m/s^2)
5. ## physics

Two point charges of magnitude +3.0 nC and +2.0 nC respectively are placed 2.0cm apart. Calculate the resultant electric field strength at their midpont E= E1 + E2
6. ## physics

Marks: 2 Light cannot be linearly polarized by: Choose one answer. a. transmission b. reflection c. diffraction d. scattering
7. ## physics

In order to move a heavy object you must push against it with a larger force than it pushes on you. Is this true or false?
8. ## physics

A car traveling at 7.3 m/s accelerates 4.5 m/s2 to reach a speed of 11.0 m/s. How long does it take for this acceleration to occur? Answer in units of s.
9. ## physics

What is the radial acceleration of an object at a point 25 meters from the axis of rotation that has a radius and a period of .22 seconds?
10. ## physics

(needed for my strain calculations) is the percentage uncertainty in a ruler 0.1cm or 0.1mm? Please answer quick.
11. ## honors physics

What is the minimum velocity for a tolerant coaster traveling on the ground to make it over 112 m hill
12. ## PHYSICS

What's the total mechanical energy of a 300kg satellite in circular orbit 1400km above Earth's surface?
13. ## physics

What is the minimum velocity needed for a roller coaster , traveling on the ground , to make it over a 112 m hill?
14. ## physics

Please Help!! How much power is developed by a jumbo jet that cruises at 250 m/s. When the trust of its engine is 100,000 N? Thanks!!!
15. ## physics

The minivan your mom lets you drive accelerates from 12 m/s to 24 m/s in 6.5 s. How far does it travel in this time? Assume constant acceleration.
16. ## Physics

Repairing a spaceship CJ drops a hammer and it took .68 s to fall .90 m to the ground. What is the magnitude of the gravitational accerleration on mars
17. ## physics

Determine the magnitude of the force of gravity acting on a 340 kg satellite , 850 km above Earth's surface.
18. ## physics

Explain the interference due to thin flims and ahows that the reflected and transmitted systems are complementary to each other.
19. ## physics

the current through a meter movement is 150 micro amperes. what is the dc value if the instrument uses half-wave rectification?
20. ## Physics

Two astronauts, one of mass 61 kg and the other 82 kg, are initially at rest in outer space. They then push each other apart. How far apart are they when the lighter astronaut has moved 12 m?
21. ## algebra based physics

Two protons in a nucleus are separated by 8.0×10−15m . What's the potential energy of the pair?
22. ## physics

In a new scenario, the block only makes it (exactly) halfway through the rough spot. How far was the spring compressed from its unstretched length?
23. ## physics

A 0.150-kg ball, moving in the positive direction at 12 m/s, is acted on by the impulse of 4N*s what is the balls final velocity

What is the current produced by a potential difference of 240 volts through a resistance of 0.2 ohms?
25. ## physics

1) How many seconds does it take a car traveling 40 mph, decelerating at a rate of 7 miles per second, to come to a complete stop? 2) How many feet?
26. ## physics

at what angle with respect to the horizontal should the shot put be launched if the starting height is 2.0m to have the greatest range?
27. ## physics

Using a small pendulum of length 0.171 m, a geophysicist observes that it completes 1 cycle every 0.833 s. What is the value of g at his location?
28. ## physics

what minimum speed does a 100g puck need to make it to the top of a 3m long 20degree frictionless ramp?
29. ## Physics

Q1:Find the phase and group velocities of the de Broglie waves of an electron whose kinetic energy is 500kev?
30. ## Physics

consider a pair of planets that find that the distance between then is decreased by a factor of 5. Show that the force between them becomes 25 times as strong.
31. ## Physics

if a molecules in a solid has a temp of T = hf/2k then what would be the average energy of vibration 1) 0.88kT 2) 0.47kT 3) 0.62kT 4) 0.31kT
32. ## Physics

While analyzing a sample of one, geologist finds that it weighs 2n in air and 1.3N when immersed in water. Calculate the density of the one
33. ## physics

A 25HP electric motor turning a 1800 RPM will produce how many foot pounds of torque?
34. ## Physics

What is the repulsive electrical force between two protons in a nucleus that are 5 x 10^ -15 m apart from each other? Could you help me with this problem? I can't figure out how to do this. Use Coulomb's equation F= kQQ/r^2
35. ## Physics

Two astronauts, one of mass 61 kg and the other 82 kg, are initially at rest in outer space. They then push each other apart. How far apart are they when the lighter astronaut has moved 12 m?
36. ## Physics

A person is jogging at 3.5 m/s and grabs a rope that is hanging vertically from a tree. How high can the student swing?

Two nitrogen atoms are separated by 4 cm. Each atom has 2 extra electrons. What is the force between them? is it attractive or repulsive? Explain.
38. ## Physics

Assuming that your lungs can function when under a pressure of 11 kPa, what is the deepest you could be under water and still breathe through a tube to the surface?
39. ## Physics

A picture hangs on the wall suspended by two strings, as shown in the figure, with θ = 59°. The tension in string 1 is 1.9 N.
40. ## Physics

Three resistors 2.5 Ù, 3.5 Ù and 4 Ù are connected in parallel. What is the equivalent resistance? I know you must use 1/Req = 1/R1 + 1/R2 + 1/R3 But then I get .935 and I don't think that's correct. What am I missing? Thanks
41. ## Physics

How do you calculate the magnitude of the uncertainty of the net force, U{F}? I was given several different equations but for some reason I'm still confused. Any help would be greatly appreciated.

When a 0.35 kg baseball is hit, its velocitychanges from 21 m/s to -29.5 m/s. What is the magnitude of the impulse de-livered by the bat to the ball? Answer in units of N · s
43. ## Physics

A tennis ball is released at 30 degrees. It reaches max height of 20 ft find initial speed
44. ## physics

A 1600 kg car travels at a speed of 10.5 m/s. What is its kinetic energy? Assume that air resistance is negligible.
45. ## physics help

how much work must be done to raise a 5kg block of steel from the ground to a height of 2m (in Joules) in the absence of friction?
46. ## Physics

If a person can have a hang time of .75 seconds, how long would it take that individual to go from the ground to the highest point of their jump?
47. ## Physics

A car accelerates at a constant rate from 13m/s to 25m/s in 6.0seconds. What was its acceleration? How far did it travel in this time?
48. ## Physics

How does an electric motor work, linking to the theory of electromagnetism? I have already identified a few laws: -Ohms -Faraday's
49. ## Physics

If the ball is tossed upward at 20 m/s, how long should it take before it reverses its direction (reaches its maximum height where its velocity is zero)?
50. ## Physics

A man carries a 10 kg sack of groceries in his arms with a force of 50 N as he walks forward a distance of 10 m. How much work has he done?
51. ## Physics

Which object produces energy in the form of light? A Venus B the sun C the moon*** D Halley’s comet I think it is C, but I'm not sure!
52. ## physics

if a skydiver with a surface area of 2m sq falls at a steady speed of 55m/s with a force of 900N what is the pressure on her?
53. ## Physics

What is the force needed to start a 100 kg block sliding on a horizontal if the coefficients for static and kinetic are 0.75 and 0.5
54. ## Physics

What, roughly, is the percent uncertainty in the volume of a spherical beach ball whose radius is r=4.84±0.05m? I keep getting 6% and it says i am wrong.
55. ## Physics

calculate the initial speed of a bicyclist whose final velocity is 20m/s if he accelerates at a rate of 2 m/s2 in 5 seconds?
56. ## physics

Why do many musicians wear earplugs during their performances even though the intensity of the sounds produced is lower than the threshold of pain?
57. ## *physics*

what is the smallest time in which a 9.00kW motor can lift a 3500 kg elevator to a height of 9.50m? use 10m/s^2 as g.
58. ## Physics

A brick has mass 10kg and dimensions (10*5*20)cm Find the maximum and minimum pressure it can exert on ground
59. ## physics

Two forces of the same magnitude act at a point.the square of their resultant is 3 times the product of their magnitudes.the angle between them is?
60. ## Physics

A period pulse travel a distance at 20m in 1•00sec,if it's frequency is 2•0×10.calculate the wave length
61. ## physics

Two equal masses m are place at positions r©û= (L, 2L, 3L) and r©ü= (3L, L ,2L). Calculate the moments of inertia Ix, Iy, Iz of the system with respect to the x, y, and z axes.
62. ## physics

A satellite orbits at an average altitude of h = 409 km. What is its orbital speed? Use REarth = 6370 km and mEarth = 5.98 x 10^24 kg
63. ## physics

A 102-kg man stands in an elevator that has an upward acceleration of 4.1 m/s2. The magnitude of the force exerted by him on the floor is about (g = 10 m/s2):
64. ## Physics

An object is dropped from rest. What is its instantaneous speed when it has been in motion for 5 s? The acceleration of gravity is 9.8 m/s2 . Answer in units of m/s
65. ## Physics

What is the acceleration of a skateboard down a ramp inclined at 19.5 degrees to the horizontal? 3.271 is the answer. This shouldn't be too tough, but I can't get it. Thanks!
66. ## Physics

Two objects attract each other gravitationally with a force of 2.1×10−10 N when they are 0.21 M apart. Their total mass is 4.00 KG Find their individual masses. .
67. ## Science Physics

How many Btu of heat must be added to 1200 lb of copper to raise its temperature from 100°F to 450°F
68. ## Physics

A ball is thrown vertically into the air with a velocity of 10ms to the negative 1 power. What will its displacement be after 1.5 seconds?
69. ## physics

Why do many musicians wear earplugs during their performances even though the intensity of the sounds produced is lower than the threshold of pain?
70. ## St. Basil's school. Physics

The time period of two pendulums are 1.44s and 0.36s respectively. Calculate the ratio of their lengths.
71. ## Physics

A car accelerates from rest at 2.9 m/s^2. How much time does it need to attain a speed of 4 m/s? Answer in units of s. are you supposed to divide 2.9 by 4?
72. ## PHYSICS

--------------A /l\ / 1 \ / 1 \ / 1 \ 1 B C the pendulum has a string of .075m. velocity at c is 3.83m/s how do i find the speed at point b when the angle of B and C is 37 degree
73. ## Physics

Two point charges that have charge values of 4.0 X 10^-6 C and -8.0 X 10^-6 C, respectively, are separated by 2.4 X 10^-2 m. What is the mutual force between them, given that kC = 8.99 X 10^9 Nm^2/C^2? I got the Felectric as -5.0 X 10^2 N, but I'm not sure
74. ## hi

Find the book's acceleration (positive for up, negative for down). .... physics An object with mass m = 20 kg is released from a height h = 60 m above the ground.
75. ## physics

Two point charges 1.5 cm apart have an electric potential energy -150 mu J. The total charge is 34 nC. what are q_1 and q_2?
76. ## physics

How much current is drawn by a television with a resistance of 21 that is connected across a potential difference of 120 V? 5.45A wasn't right
77. ## physics

A 2.0kg book is lying on a 0.74m high table. You pick it up and place it on a bookshelf 2.0m above the floor
78. ## physics

an ant walk 1 meter west and then 3 meters north whats is the ants direction in degrees
79. ## physics

if a train travell at speed of 90km/hour. and when the break applied at 5m/sec2. how much it will travel before stoping
80. ## Physics-Electricity

Consider three charged particles placed along the x-axis. The particle with q1 = 9.30 nC is at x = 6.87 m and q2 = 4.09 nC is at x = 0.600 m. Where must a positive charge, q3, be placed such that the resultant force on it is zero? x=?m
81. ## Physics

a bus moving at a speed of 20m/s begins to slow at a constant rate. Find how far it goes before stopping?
82. ## PHYSICS

What is the reaction effect of the following action effects? a) Earth orbits the sun b) Ball accelerates downward Thank YOu.
83. ## Physics

A Ping-Pong ball has a mass of 2.3 g and a terminal speed of 8.2 m/s. The drag force is of the form bv2 What is the value of b?
84. ## Physics

You're sailboarding at 7.0 m/s when a wind gust hits, lasting 6.8 s accelerating your board at 0.47 m/s2 at a 35 degrees to your original direction.
85. ## Physics

A 100kg steel beam falls from rest from a height of 20m, Find its impact speed.
86. ## PHYSICS

Calculate the maximum amount of stretching (in percent) that a piece of steel can undergo before breaking under tension
87. ## physics - ohms law

how hot would a copper wire need to be for its resistance to be 2% larger than its value at room temperature (20 Centigrade)?
88. ## physics

Beats in sound are the result of which of the follwing wave? A) resonance.B) refraction.C) reflections.D) amplitude changes.E) interference
89. ## physics

What is the required resistance of an immersion heater that will increase the temperature of 2.00 kg of water from 10.0°C to 50.0°C in 9.0 min while operating at 120 V?
90. ## Physics

is the mechanical energy of a teflon coated block sliding down a rough incline remaining constant?
91. ## physics

if a bus traverses a distance of 10,000 cm with the uniform velocity of 10 m/sec, what is its total time of travel?
92. ## physics

a waterfall is 122 m in height. calculate the rise in temperature if all potential lost is converted to heat.
93. ## Physics

What capacitance in needed in series with an 785 µH inductor to form a circuit that radiates a wavelength of 199 m?
94. ## physics

the substance which allows heat radiations to pass through is.a)iron b)water vapour c)wood d)dry air
95. ## physics

A 71.1 kg man steps out a window and falls (from rest) 1.24 m to a sidewalk. What is his speed just before his feet strike the pavement?
96. ## Physics

Some propane occupies 150 cm^3 at 12.4°C. Find the temperature when its volume is 132ft^3 if the pressure remains constant.
97. ## Physics - waves

What is the source of wave motion? I would think it would be an object such as a rock dropping in the water. How this translates into an answer, however, I'm not sure. :-)
98. ## Physics

To suck water up a straw to a maximum height of 98 mm, what minimum gauge pressure must be produced in the lungs?
99. ## physics

an electric motor lifts on elevator 9 m in 15s by exerting an upward force of 1.2 x 10^4 calculate the power
100. ## physics

consider a pair of planets that find the distance between them is decreased by a factoer of 5. Show that the force between them becomes 25 times as strong?