# Math/Physics

215,206 results, page 85

1. ### physics

A sharp image is located 83.0 mm behind a 62.0 mm focal-length converging lens. Find the object distance by calculation.
2. ### PHysics

What is the total energy of a 15-kg mass attached to a spring oscillating horizontally with an amplitude of 20 cm and an angular frequency of 32 rad/s?
3. ### Physics

Describe the waves reflected from an elliptical reflector when the incident wave comes from a point source at one focus of the ellipse?
4. ### physics

An airplane has a velocity of 185 miles per hour when it lands, how long must the runway be if the plane decellerates at 2.5 meters per second
5. ### Physics

When you swim across a river does the time it takes to get to the other side depend on the rate of flow of the water? Defend your answer.
6. ### Physics

Neglecting air resistance, how high could a 0.15kg baseball be thrown if it is throw straight up at a speed of 25m/s?
7. ### Physics

An airplane starts from rest and accelerates at a constant rate if 3.00m/s^2 for 30.0s before leaving the ground. A)How far did it move? B) how fast was it going when it took off?
8. ### Physics

A pulley system has a velocity ratio of 4 and an efficiency of 80%.calculate the value of the effort required to raise the load of 480N
9. ### physics

During an Olympic bobsled run, the Jamaican team makes a turn of radius 7.9 m at a speed of 97.4 km/h. What is their accelaration in g-units?
10. ### physics

How much would the time keeping of a pendulum clock be affected by taking it to the moon? Gravity is 1.6m/s ^2, compared with 10m/s ^2 on the earth.
11. ### physics - forces

Calculate the velocity of a satellite moving in a stable circular orbit about the Earth at a height of 2600 km.
12. ### Physics

Calculate the net charge on a substance con- sisting of a combination of 1.9 × 10^13 protons and 3.9 × 10^13 electrons. Answer in units of C.
13. ### Physics

What is the upper tripper point (UTP) of a comparator with hysteresis if R1 = 47 kÙ, R2 = 68 kÙ and the maximum positive output voltage is 10V?
14. ### physics

A rocket is fired with an initial velocity of 200m/s at an angle of 60' to the horizontal.Find (1)the maximum height reached.
15. ### Physics

Simple Harmonic Motion With the equation x=Acos(2 pi f) t why and how does f affect x This is really urgent! Thanx for any help! frequency determines how rapidly x oscillates.
16. ### physics

what is the length of the shortest pipe closed on one end that will have a fundamental frequency of 60 hz on a day when the velocity of sound is 340 m/s?
17. ### Physics

At what distance should an object be placed in front of a convex lens of focal length 20 cm to obtain an image of double its size
18. ### Physics

Which object has a greater momentum, a stationary tractor-trailer or a tossed tennis ball? Explain your answer please.
19. ### Physics

A boy of mass 50kg running at 5m/s jums on to a 20kg trolly travelling in the same direction at 1.5m/s .what is their common velocity.
20. ### Physics

Why would normal force be set to zero to calculate the minimum possible speed a rider can have at the top of a loop. Please i need help, this is due in few hours
21. ### physics

A 2.284 km car is moving down a road with a slope of 13% at a constant speed of 11 m/s. What is the direction and magnitude of the frictional force?
22. ### Physics

A student travels 6.0 m [E] in 3.0 s and then 10.0 m [N] in 4.0 s. Draw a vector diagram to determine the resultant displacement. Q: How do you know where the starting point is on the graph?
23. ### physics

How does the presence of an atmosphere affect the length of day and night? I am thinking by the rising and setting of the moon and sun. Is this right? Thank You.
24. ### Physics

Two objects attract each other gravitionally with a force of 2.5 *10^-10 N when they are .25m apart. Their total mass is 4.0kg. Find their individual masses.
25. ### Physics

“Strontium-90 is a pure beta source.” How could a physicist test this statement? I am stuck on this one, but I was thinking through measurement of radioactivity.
26. ### Physics

A large merry-go-round completes one revolution every 17.5 s. Compute the acceleration of a child seated on it, a distance of 5.80 m from its center.
27. ### physics

Who developed modern periodic table? Descibe particle arrangements & movement for each phase of matter. (Thank you for helping me)
28. ### physics

draw a particle model and a motion diagram for A bike travels at constant speed of 4.0 m/s for 4 s then slow down to come at rest in 3 s.
29. ### Physics Help

An electron with velocity v = 2.4 × 106 m/s i encounters an electric field E = 1250 N/C i. How long will it take for the speed to be one fourth its original value?
30. ### Physics

What force is required to accelerate an object of 1.484x10^0 kg over a frictionless surface at -2.3580x10^0 m/s2 expressed to three significant figures.
31. ### physics

consider an electron near the equator. in which direction does it tend to deflect by the magnetic field of the earth if its velocity is directed a.northward
32. ### Physics

How does Rutherford's model of the atom account for the back-scattering of alpha particles directed at the gold foil?
33. ### Physics

Calculate the net charge on a substance con- sisting of a combination of 1.9 × 10^13 protons and 3.9 × 10^13 electrons. Answer in units of C.
34. ### physics 101

What minimum speed does a 150g puck need to make it to the top of a 4.5m -long, 21degree frictionless ramp?
35. ### Physics

What is the minimum work in joules needed to push a 1840 kg car 14.0 m up a 12.5 degree incline? (Ignore friction.)
36. ### physics

If a 2000 pound train tilts of a 20 foot cliff at a 135 angle how long will it take to reach the ground?
37. ### physics

A body moves with uniform acceleration with a distance x for 1st sec. What is relation b/w x & y? A) y=24x B) y=16x C) y=12x D) y=8x
38. ### Physics

A 45 kg child sits on a 5 kg sled and slides down a 117 meter, 31 degree slope, to the nearest m/s what is his or her speed at the bottom?
39. ### Physics

If a ball is kicked at 35 degrees above the horizontal, what is the speed to barely clear the 3m tall goal post 60m away?
40. ### physics

n boat starts from rest and accelerates at a constant rate to a final speed of 28 m/s over a distance of 780 m. How much time will this take?
41. ### physics

How many revolutions per minute would a 15 -diameter Ferris wheel need to make for the passengers to feel "weightless" at the topmost point?
42. ### Physics

Determine the stopping distances for a car with an initial speed of 93 km/h & human reaction time of 0.80 s, for an acceleration a=−4.0m/s2.?
43. ### science (physics)

A body travels 10m in 5th second and 30m in 10th second. Find its initial velocity and acceleration.
44. ### physics

for an 84 kg person standing at the equator what is the magnitude of angular momentum about the earths center due to earth's rotation
45. ### Physics

conical pendulum is formed by attaching a 0.200 ball to a 1.00 -long. It has a radius of 40.0cm . What is the tension in the string?
46. ### Physics

conical pendulum is formed by attaching a 0.200 ball to a 1.00 -long. It has a radius of 40.0cm . What is the tension in the string?
47. ### Physics HELP!!!

A ball is kicked at an angle of 50 with a velocity of 14m/s. a. how long is it in the air? b. how high does it rise? can someone please explain to me how to solve this???
48. ### Physics

A Ferris wheel has a radius of 14 m. What period of rotation would give the occupants a feeling of "weightlessness" at the top? __s
49. ### physics

A boy of mass 50kg runs up a set of stairs of total height of 3.0m.find the work done against gravity
50. ### physics

A particle is projected with a speed of 25 m/s at an angle of 40 degrees above the horizontal. "What is the time taken to reach the highest point of trajectory?"
51. ### physics

A particle is projected with a speed of 25 m/s at an angle of 40 degrees above the horizontal. "What is the time taken to reach the highest point of trajectory?"
52. ### physics...one last time

A mortar elevated to 60 degrees scores a hit 15 m up a building 30m away. with what speed was the shell fired?
53. ### physics

Explain how you can tell the following statement is false A neutron was moving in a circle while speeding up. As a result, gamma rays were emitted.
54. ### physics

a car traveling in a straight line has a velcoity of 2.43 m/s at some instant. After 6.73 s, its velocity is 9.81 m/s. what is its average acceleration in this time interval?
55. ### Physics

A real spring does not oscillate forever. Instead, it eventually comes to a stop. Does this violate the Law of Conservation of Energy? Explain why or why not.
56. ### physics

how long will it take a 1750-watts motor to a lift a 285-kg piano to a sixth storey window 1.6 meters above
57. ### physics

An 87.0 kg fullback moving east with a speed of 5.0 m/s is tackled by a 83.0 kg opponent running west at 2.92 m/s, and the collision is perfectly inelastic.
58. ### Physics

A bean jumps vertically off of a table. It has a speed of 10 m/s when it reaches half of its maximum height. How high does it rise?
59. ### physics - magnetism

A positive and a negative particles enter magnetic field at the same angle and with the same velocity. How different would be the path of each particle?
60. ### physics

If the breakers at a beach are separated by 5m and hit shore with frequency of 0.3Hz, at what speed are they travelling? Please show all work, Thank you
61. ### Physics

A 84.0-kg airplane pilot pulls out of a dive by following, at a constant speed of 163 km/h, the arc of a circle whose radius is 312.0 m.
62. ### physics

A wooden cube of side 10cm has mass 700g.What part of it remains above the water surface while floating?
63. ### Physics

How long will it take a motor with an output power of 4000 W to lift a 250 kg container vertically upwards 25 m? how would u do the calculation?
64. ### physics

The difference in energy between allowed oscillator states in HBr molecules is 0.330 eV. What is the oscillation frequency of this molecule?
65. ### Physics

A 70 kg waterslide rider traveling at 15 meters per second hits a ramp with a 58 degree launch angle - How high will they fly?
66. ### Physics

What is the max speed a car can go on a race track with a radius of 80 meters, the coefficient of friction between the tires and the road is .30
67. ### physics

In the following list of periodic waves, which one is independent of the others: frequency, wavelength,speed,amplitude? Plese show all work Thank you
68. ### Physics

if light touching a surface has an intensity of about 1000W/m^2, how many numbers of photons per m^2 per sec does this show? wavelength of P=600nm
69. ### physics

formulation of hypothesis for the prepation of a standard solution of oxalic acid with a concentration of 0.05mol.dm3. very desperate
70. ### physics

A pendulum has a mass of 3-kg, a length of 2 meters and swings through a (half)arc of 27.3 degrees. What is its Amplitude to the nearest centimeter ?
71. ### Physics

conical pendulum is formed by attaching a 0.200 ball to a 1.00 -long. It has a radius of 40.0cm . What is the tension in the string?
72. ### Physics

the 8kg mass of an object moves in a distance of radius 10cm at 15m^2.calculate the angular velocity
73. ### Physics

A satellite is to be put into a circular low earth orbit at 149 km above surface. What orbital speed (km/s) is required?
74. ### physics (science)

A body travels from rest with acceleration 8m/s square . Find its velocity when it has covered a distance of 100m
75. ### Physics

A body is projected at angle of 30 degree with the horizontal at an initial speed of 200m/s.how far from the point of projection will it strike
76. ### Physics

Problem 3- If a bug can jump straight up to a height of 0.5 m. a) what is its initial speed as it leaves the ground? b) How long is it in the air?
77. ### Physics

Touching a Van de graff generator and slowly moves away from the dome why he touches it again he recives a stron shock why ?
78. ### physics

A female gymnast weighs 200 N. If she is hanging stationary from a high bar,how many forces are acting on her? A. one B.five C.four D.two E.three WOuld it be choice A or D?
79. ### Physics

Calculate the yearly cost of running a 6 W electric clock continuously in a location where energy costs 12 cents per kW · h.
80. ### To rajesh jain

Do not post any question more than once. Currently, I don't see any physics tutors online. Please be patient and wait for them to find what you have already posted.
81. ### Physics

A construction worker exerts 209N to move a load of bricks a distance of 10m across the parking lot,

An airplane that can fly at 300 km/hr is flying at 210 when it is hit by a wind of 125 km/hr at 110. What is the new velocity of the plan?
83. ### physics

Explain how you can tell the following statement is false A neutron was moving in a circle while speeding up. As a result, gamma rays were emitted.
84. ### Physics

Standing on a bridge, you throw a 3.0 g stone straight upward with speed of 2.5 m/s. How long does it take to return to the original position?
85. ### Physics

16) A curve of radius 120 m is banked at an angle of 18°. At what speed can it be negotiated under icy conditions where friction is negligible? 2 m/s 12 m /s 20 m /s 5 m/s 11 m/s
86. ### Physics

How much time is needed to completely stop a 1600 kg car moving at 35 m/s if an average force of 4200 n is applied?
87. ### Physics

A baseball was hit at 45m/s at an angle of 45 degrees above the horizontal. How long did it remain in the air? How far did it travel horizontally?
88. ### Physics

Does the frequency of light change as it enters a different substance? I know that the speed changes. The question might seem easy, but I have contradicting notes, so I'm confused.
89. ### physics

a car traveling in a straight line has a velcoity of 2.43 m/s at some instant. After 6.73 s, its velocity is 9.81 m/s. what is its average acceleration in this time interval?
90. ### physics

explain the scientific method for dropping a penny from the empire state building to see if it will penetrate someones head below
91. ### physics

At high speeds, a particular automobile is capable of an acceleration of about 0.510 m/s^2. At this rate, how long (in seconds) does it take to accelerate from 95.0 km/hr to 101 km/hr?
92. ### Physics

What is the linear speed of a child standing 0.4 m from the centre of a steadily rotating merry go around? It makes one complete revolution in 16.0 s.
93. ### physics

Show that 480 W of power is expended by a weightlifter when lifting a 60-kg barbell a vertical distance of 1.2 m in a time interval of 1.5 s.
94. ### Physics

1. What is happening to that air between the instruments and your ears? 2. How can you produce the change in the frequency? 3. Describe how the notes are produced in a violin?
95. ### Physics help

How fast would you need to be travelling relative to an observer in order for them to see a 15% increase in your mass? How do I rearrange the formula to solve for v m = n/sqrt(1-(v^2)/c^2))
96. ### Physics

Two identical loudspeakers are 2 m apart. A person stands 4.6 m from one speaker and 3.4 m from the other. What is the lowest frequency at which destructive interference will occur at this point?
97. ### physics

a bullet initially moving with a velocity 20m/s strikes a target and comes to rest after penetrating a distance 10cm in
98. ### Physics

An unbalanced forced of 2.5x10^3N is applied to an object with a weight of 3.0x10^3N on a frictionless surface. What is the objects acceleration?
99. ### physics repost

A 1.00-kg ball is attached to a string of 0.50 m and swung in a horizontal circle with a velocity of 2.00 m/s. Find the centripetal acceleration. ac=v^2/r = 2.00^2/.50 = 8.0 m/s^2
100. ### mathematical physics

Separate the following partial differential equation into a set of three ODEs by the method of separation of variables: d^2u/dt^2 =c^2,[d^2u/dr^2+1/r du/dr+1/r^2 d^2u/d theeta^2]