# Math/Physics

214,413 results, page 98

1. ### physics

a rock climber weights 550N and is carrying a backpack that weighs 50N. how much total work has been done after she climbs 12m
2. ### physics

using a sketchs, show the type of directions of forces acting on the following farm hand tools i) a hoe ii) a rake for land clearing 0
3. ### Physics

A force of 250 N is just sufficient to start a 50 kg steel trunk moving across a wooden floor. Find the coefficient of static friction.
4. ### Physics

The heat of fusion of water is 80 cal/g. When 25 g of ice at 0ºC is placed in the contents of a 12 oz can of Coke (≈350 g) at 25ºC, what is the final temperature of the beverage?
5. ### physics

A ball is dropped from a high building. Using the approximate value of g = 10 m/s2, find the change in velocity between the fourth and seventh second of its flight
6. ### physics

How deep can a snorkel diver dive if the maximum gauge pressure on the thorax cannot exceed 10.9 kPa? Hint: density of seawater = 1.015g/cm3
7. ### physics

Two equals negatives charges (-1.75x10^(-19) Coulb) are separated by an insulator at a distance of 0.230 mm. Find the electrostatic force between these electrons?
8. ### 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.
9. ### physics

Two forces are applied to a car in an effort to move it, as shown in the following figure, where F1 = 416 N and F2 = 363 N. (Assume up and to the right as positive directions.)
10. ### physics

If the coefficient of kinetic friction between tires and dry pavement is 0.800, what is the shortest distance in which an automobile can be stopped by locking the brakes when traveling at 25.7 ?
11. ### 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?
12. ### 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=?
13. ### Physics

You throw a baseball straight up at 40 m/s and it reaches its peak after 4.00 seconds. What is its speed when it falls back into your hand? What is its displacement? What distance has it traveled?
14. ### physics

According to newtons 1st law , construction workers are warned not to leave their hard hats on the rear window ledge of their cars, explain why?
15. ### physics

Qualitatively explain how you would expect the kinetic energy to change as a glider slides down an inclined air track, where friction is negligible.
16. ### 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.
17. ### physics

If the coefficient of kinetic friction is 0.25 , how much horizontal force is needed to pull each of the following masses along a rough desk at a constant speed? A) 25 kg
18. ### Physics

A triply ionized beryllium atom (Be3+) has only one electron in orbit about the nucleus. What is the radius of the ion when it is in the n = 9 excited state?
19. ### physics

two perfect elastic balls of same mass m are moving with velocities u1 and u2 . they collide elastically n times. the kinetic energy of the system finally is?
20. ### physics

determine the static coefficient of friction if a box will be rasied at rest, right up until the point that the board on which it is sitting gets raised to 53 degrees.
21. ### physics

a circular wire loop of radius 5cm lies in the xy-plane in a magnetic field defined by B=-(4t^2+3t).determine the voltage across the resistor at time t=2s
22. ### 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.

A bus moving with speed 0.93c is 65 feet long according to its passengers and driver. What is its length from your vantage point on a fixed planet?

The two-mile linear accelerator at Stanford University in California "appears" to be less than a meter long to the electrons that travel in it. Explain.
25. ### physics

two objects of masses m1 and m2 fall freely from height h1 and h2 in a vertical plane respectively.The ratio of time taken by them is how much by reaching the ground?

question # 1 :Estimate the work you do to mow a lawn 13m by 23m with a 60cm wide mower. Assume you push with a force of about 15 N
27. ### Physics

The minimum frequency for the photoelectric effect of a zinc plate is 9.7 × 1014 Hz. What will be the kinetic energy of an ejected electron when a photon with a wavelength 200 nm (2.00 × 10 7 m) strikes it?
28. ### Physics

A 6.25 kg solid ball with a radius of 0.185 m rolls without slipping at 3.55 m/s. What is its total kinetic energy? I didn't understand what the last person gave me for help can someone please help me!
29. ### Physics

An airplane flying at 82km/hr at 30 degrees east of north encounters a 40km/hr wind due west. What is the speed of the plane relative to the ground?
30. ### Physics

An object slides down a frictionless 33 degree incline whose vertical height is 54.0 cm. How fast is it going in meters/second when it reaches the bottom?
31. ### physics

A baseball is thrown horizontally off a cliff with a speed of 11 ms^-1. What is the vertical distance, to the nearest tenth of a meter, that the ball has fallen after 4.8 seconds?
32. ### physics

A spherical baloon expands when it is taken from the cold outdors to the inside of a warm house. if its suface area increases 16%, by what percentage does the radius change
33. ### physics

The highest George can suck water up a very long straw is 2.0m What is the lowest pressure he can maintain in his mouth? Express to two sig figs
34. ### physics

What is the magnitude of the electrostatic force that the two protons inside the nucleus of a helium atom exert on each other? Why do atomic nuclei not simply explode?
35. ### physics

a ball is thrown upward what is its maximun height? its initial vertical speed is 8.1 m/s and the acceleration of gravity is 9.8 m/s . neglet air resistance . answer in units of m
36. ### physics

a car travelled 1/3 of the way between two citties with speed of 80 km/hr, then continues moving with 130 km/hr. find his average velocity for the whole trip
37. ### physics

A diver jumps off a diving board with a speed of 25m/s he returns to the water after 3s. At the top of his dive describe his velocity and his acceleration?
38. ### physics

determine the acceleration for a jet taking off on a run way as it starts from rest and reaches a velocity of 50m/s over a period of 10s
39. ### Physics

On some planet other than Earth a ball is thrown upward at a velocity of 22.3 m/s. It returns back to the exact position that it started at in 8.8s. What is this planets value for "g"? (
40. ### Physics

a 150-N and 80-N force act upon an object. the angle between the two forces is 55 degrees. determine the magnitude and direction by trigonometric calculations.
41. ### physics

You drive a car 2.0 km to the gas station, 4.0 km to the shopping mall to let your mother off, and 4.5 km back home. The trip takes 20.0 min. What is your average speed?
42. ### 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?
43. ### PHYSICS

(a) how long it took King Kong to fall straight down from the top of a 210 m high building s (b) his velocity just before "landing"
44. ### physics

A ball is thrown vertically upward with a speed of 24.7 m/s from a height of 2.0 m. How long does it take to reach its highest point? The acceleration of gravity is 9.81 m/s 2 . Answer in units of s
45. ### physics

A ball is thrown vertically upward with a speed of 24.7 m/s from a height of 2.0 m. How long does it take to reach its highest point? The acceleration of gravity is 9.81 m/s 2 . Answer in units of s
46. ### physics

A rocket moves upward, starting from rest with an acceleration of 32.0 m/s2 for 3.27 s. It runs out of fuel at the end of the 3.27 s but does not stop. How high does it rise above the ground?
47. ### science[physics]

three masses 3kg,4kg,5kg are located at corners of an equilateral triangle of side 1m.locate the centre of mass of the system
48. ### Physics

1. 125g mass attached to a string oscillates with an amplitude of 7.8cm and a maximum speed of .625 m/s. Find (a) the force constant and (b) the period of motion.
49. ### physics

For a given velocity of projection in a projectile motion, the maximum horizontal distance is possible only at ө = 45°. Substantiate your answer with mathematical support. 20.5 m/s
50. ### Physics

A heavy freight train has a mass of 13200 metric tons. If the locomotive can pull with a force of 755000N, how long does it take to increase it's speed from 0 to 95.5 km/h?
51. ### Physics

The coefficient of kinetic friction for a 34.3 kg bobsleigh on a track is 0.150. What external force is required to push it down a 5.60° incline and achieve a speed of 60.12 km/h at the end of 75.2m ?
52. ### physics

A 0.5 kg block is sliding along a table top with an initial velocity of 0.2 m/s. It slides to rest in a distance of 70 cm. Find the frictional force that is slowing its motion.
53. ### Physics

Suppose the surface (radius = r) of the space station in the figure is rotating at 38.6 m/s. What must be the value of r for the astronauts to weigh one-half of their earth-weight?
54. ### Physics

Suppose the surface (radius = r) of the space station in the figure is rotating at 38.6 m/s. What must be the value of r for the astronauts to weigh one-half of their earth-weight?
55. ### Physics

Suppose the surface (radius = r) of the space station in the figure is rotating at 38.6 m/s. What must be the value of r for the astronauts to weigh one-half of their earth-weight?
56. ### Physics

A crate with a mass of 40 kg is being dragged along a horizontal floor at a constant velocity by an applied force of 180 N. What is the coefficient of kinetic friction? (g = 10 m/s2
57. ### Physics

A stone is thrown from the ground with initial velocity v0 directed at angle alpha with respect to the horizon. Find equations of its motion both in x and y directions.
58. ### Physics

A ball is thrown vertically upward with a speed of 26.1 m/s from a height of 2.1 m.How long does it take to reach its highest point? The acceleration of gravity is 9.81 m/s2. Answer in units of s
59. ### physics

Jessie exerted a force of 400N to move a box across the floor to a distance of5m in 4sec. What is his power is kilowatts? Megawatts? Horsepower?
60. ### physics

Jessie exerted a force of 400N to move a box across the floor to a distance of5m in 4sec. What is his power is kilowatts? Megawatts? Horsepower?
61. ### physics

Jessie exerted a force of 400N to move a box across the floor to a distance of5m in 4sec. What is his power is kilowatts? Megawatts? Horsepower?
62. ### physics

Jessie exerted a force of 400N to move a box across the floor to a distance of5m in 4sec. What is his power is kilowatts? Megawatts? Horsepower?
63. ### physics

A large block P executes horizontal simple harmonic motion as it slides across a frictionless surface with a frequency f = 0.3 Hz. (a) What is the angular velocity of this system?
64. ### Physics

two equal charges exert an elecrtric force on each other of 0.0385N when positioned 0.15m apart determine the magnitude of the charge on each point.
65. ### physics

1. During storm roof of house is blown off 2.It is dangerous to stand near the railway track when a train is moving with high speed
66. ### physics

An object is projected upward from the surface of the earth with an initial speed of 2 km/s. The acceleration of gravity is 9.81 m/s^2. Find the maximum height it reaches. Answer in units of km.
67. ### physics

A roller coaster car is moving at 20.0m/s along a straight horizontal track. what is the speed after climbing a 15.0m hill? neglect the effects of friction
68. ### physics

An object is placed 5 cm in front of a concave lens of focal length 7 cm. Find the image location by drawing a ray tracing diagram to scale.
69. ### physics

A 224 g particle is released from rest at point A along the diameter on the inside of a fric- tionless, hemispherical bowl of radius 44 cm. The acceleration of gravity is 9.8 m/s2 .
70. ### 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.
71. ### physics

Mason lifts a box off the ground and places it in a car that is 0.50 meters high. If he applies a force of 8.0 newtons to lift this suitcase, what is the work done?
72. ### physics

whaat happens to the potential energy lost by hammer of pile driver when it falls through a distance and drives a piling into the ground?
73. ### Physics

A jet aircraft is accelerating at 4.3 m/s2 as it climbs at an angle of è = 44° above the horizontal (see figure). What is the total force that the cockpit seat exerts on the 77 kg pilot?
74. ### 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.
75. ### physics

A 10 kg mass is sitting on a 25 degree incline. A constant force of 49N is applied up the plane. The coefficient of static friction is .25. Does it go up or down or does it stay put?
76. ### physics

Two positive charges of 6.83 µC each are 673 cm apart. Find the electric ﬁeld midway between them. The value of the Coulomb constant is 8.98755 × 10 9 N · m2 /C 2 .
77. ### 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.
78. ### physics

An electron with initial speed = 2.54×10^7 m/s is traveling parallel to an electric field of magnitude = 1.66×10^4 N/C . How much time will elapse before it returns to its starting point?
79. ### 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.
80. ### 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.
81. ### physics

A 50.7 kg student climbs a 6.35 m long rope and stops at the top. What must her average speed be in order to match the power output of a 130 W lightbulb
82. ### physics

If a baseball moving at 96 m/s toward homeplate over a distance of 16 m how much force does it take to make the ball go 50 m from home plate after it is hit?
83. ### physics

wonder waves in shallow yellow disc are 6.0 cm long. at one point, the water oscillates up and down at a rate of 4.8 of oscillations per second
84. ### physics

A electric model train travels at 0.339 m/s around a circular track of radius 1.75 m. How many revolutions does it perform per second, i.e, what is the motion's frequency?
85. ### physics

A electric model train travels at 0.339 m/s around a circular track of radius 1.75 m. How many revolutions does it perform per second, i.e, what is the motion's frequency?
86. ### physics

A rocket moves upward, starting from rest with an acceleration of 30.5 m/s2 for 3.39 s. It runs out of fuel at the end of the 3.39 s but does not stop. How high does it rise above the ground?
87. ### physics

a converging lens has a focal length of 15cm. Find two positions where a real object can produce images four times its size.
88. ### physics

a converging lens has a focal length of 15cm. Find two positions where a real object can produce images four times its size.
89. ### physics

A coin is placed at a focal point of a converging lens. Is an image formed? If yes, is it real or virtual , erect or inverted, larger or smaller than the object?
90. ### physics

A 2.6-kg particle moving along the x axis has a velocity of +1.7 m/s as it passes through the origin. It is subjected to a single force, Fx, that varies with position, as shown below.
91. ### physics

An object is placed (a)6cm (b)20 from a thin convex lens of focal length 10cm.determine the nature,position and magnification of the image in each case.
92. ### Physics

A baseball is thrown horizontally off a cliff with a speed of 7.3 ms-1. What is the vertical distance, to the nearest tenth of a meter, that the ball has fallen after 9.4 seconds?
93. ### physics

when 100 J of work is done on a stationary flywheel ( that is otherwise free to rotate in place), its angular speed increases from 60 rev/min. What is its moment of inertia?
94. ### physics 1

a helicopter is flying at an altitude of 1000 m above the ground, with a horizontal velocity of 50 m/s, how far from the rally point should the relief package be dropped?
95. ### 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.
96. ### Physics

A man lifts a heavy stone using a bar supported at a stationary point. Which phenomena in daily life in terms of the scientific principles
97. ### 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.
98. ### Physics

What is the change in angular momentum of a planet with radius R if an asteroid mass m and speed v hits the equator at an angle from the west, 40 degrees from the radial direction?
99. ### 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?
100. ### Physics

How long (in seconds) would it take a sound to travel underwater across the San Francisco Bay at its widest point of 19 000 meters?