# physics

Popular questions and responses by physics
1. ## physics

At t= 0, a particle starts from rest at x= 0, y= 0, and moves in the xy plane with an acceleration ->a (vector) = (4.0ihat+ 3.0jhat)m/s^2. Assume t is in seconds. Determine the x component of velocity as a function of time t. Determine the y component of

2. ## Right Hand Rule

Consider an electron near the Earth's equator. In which direction does it tend to deflect if its velocity is directed in each of the following directions? (a) downward: WEST (b) northward . (c) westward d) southeastward I go the first one right using the

3. ## phys

An airplane is heading due south at a speed of 590 km/h. If a wind begins blowing from the southwest at a speed of 65.0 km/h (average). Calculate magnitude of the plane's velocity, relative to the ground. Calculate direction of the plane's velocity,

4. ## physics

If Vx= 8.00 units and Vy= -6.40 unis, determine (a)the magnitude and (b)direction of ->V(vector) b) theta= ______ degrees below the positive x-axis.

5. ## Physics

I have two questions this one A 750-N force acts in a northweserly direction. A secon 750-N force must be exerted in what direction so that the resultant of the two forces points westward? I have no idea how to go about solving this prolbem second Draw the

6. ## physics

please check these: A concave mirror with a focal length of 10.0 cm creates a real image 30.0 cm away on its principal axis. How far from the mirror is the corresponding object? a. 20cm b. 15cm c. 7.5cm d. 5.0cm B A diffraction grating that contains 650

7. ## PHySics

A 1.63 nF parallel-plate capacitor is charged to an initial potential difference ΔVi = 100 V and then isolated. The dielectric material between the plates is mica, with a dielectric constant of 5.00. (a) How much work is required to withdraw the mica

8. ## Physics

A crate of fruit with a mass of 37.5 kg and a specific heat capacity of 3800 J/(kg⋅K) slides 7.60 m down a ramp inclined at an angle of 38.5 degrees below the horizontal. If the crate was at rest at the top of the incline and has a speed of 2.35 m/s at

9. ## Sarah

A light spring having a force constat of 125 N/m is used to pull a 9.50kg sled on a horizontal frixtionless ice rink. If the sled has an acceleration of 2.00 m/s^2, by how much does the spring stretch if it pulls on the sled (a) horizontally, (b) at 30.0

10. ## Physics

A crate is pulled right with a force of 82.0N to the left wtih a force of 115N upward with a force of 565N and downward with a force of 236N Fine the net external force in the X direction Find the net external force in the y direction find the the

11. ## Physics

A delivery truck travels 18 blocks north, 10 blocks east, and 16 blocks south. what is its final displacement from the origin? assume the blocks are equal length. My only question is I got about 10 blocks for the displacement got a 2 opposite and 10

12. ## Physics

A 2.0 kg mass starts from rest and slides down an inclined plane 8.0 X 10^-1 m long in .50s. what net force is acting on the mass along the incline. I have no idea how to do this I don't know why they just didn't say .8m the back of the book says 13 N down

13. ## Physics

A ball is thrown horizontally from the roof of a building 9.0 m tall and lands 8.5 m from the base. What was the ball's intial speed? I have no idea how to do this problemm or what formulas to use because of the fact that I do not know the time interval it

14. ## physics

please check this: Which sentence best describes electrical conductors? a. electrical conductors have low mass density b. electrical conductors have high tensile strength c. electrical conductors have electric charges that move freely d. electrical

15. ## physics physics

Physics Question Two toy ducks, attached to each other by a string, are being pulled by a very happy guy who just got them as a graduation present (Fig. 4.31). The front duck is 5.0 kg and the back duck is 2.0 kg. If the happy guy pulls them with a force

16. ## physics

How much heat is added to 10.5 g of ice at -20.0°C to convert it to steam at 123.5°C?

17. ## Melanie

A right triangle has a hypotenuse of length 13 meters and one side of length 5 meters. What is the length of the third side and the angle between the hypotenuse and the 5 meter side? A. 144 meters, 67.38 degrees B. 12 meters, 22.62 degrees C. 10 meters,

18. ## PHYSICS

A 4.00 µF capacitor is connected to a 18.0 V battery. How much energy is stored in the capacitor? This should be a relatively easy problem yet, I can't get it. Isn't it just E=.5*C*V^2

19. ## Physics!

The cable supporting a 2100kg elevator has a maximum strength of 2.19×10^4 N. What maximum upward acceleration can it give the elevator without breaking?

20. ## physics

two point charges are 10.0 cm apart and have chargeso of 2.0 uC (micro)and -2 uC, respectively. What is the magnitude of the electric field at the midpoint between the two charges? i think i know how to do it: both E1 and E2 go in the same direction

21. ## Physics

A 50-g ice cube at is placed in an equal mass of water. What must the initial water temperature be if the final mixture still contains equal amounts of ice and water?

22. ## Physics

A Ball of Mass 0.5kg Moving At 10m/s Collide With Another Ball Of Equal mass At Rest.If The Two Balls Move Together After The Impact Calculate Their common Velocity

23. ## physics

please check these for me: If atmospheric refraction did not occur, how would the apparent time of sunrise and sunset be changed? a. both would be later b. both would be earlier c. sunrise would be later, and sunset would be earlier d. sunrise would be

24. ## Physics

A 0.400 kg block of wood hangs from the ceiling by a string, and a 0.0700 kg wad of putty is thrown straight upward, striking the bottom of the block with a speed of 6.40 m/s. The wad of putty sticks to the block. How high does the putty-block system rise

25. ## physics

Calculate the acceleration due to gravity on the moon. The moon\'s radius is about 1.74 E 6 m and its mass is 7.35 E 22 kg ok aparently there\'s an easier way to do this I applied Newtons second law in the radial direction net force radial = m (radial

26. ## Physics

A coin is placced 12.0 cm from the axis of a roatating turntable of variable speed. When the speed of the turntable is slowly incraeased, the coin remains fixed on the turntable until a rate of 50 rpm is reached at which point the coin slides off. What is

27. ## natali

A 100W light bulb is left on for 10hrs. Over this period of time how much energy is used by the bulb? am i doing this right? my guess is to convert 100W to kW and convert 10 hrs to seconds and multiply the 2 together? which gives 3600J or should i just

28. ## micole

White light strikes a diffraction grating (930 lines/mm) at normal incidence. What is the longest wavelength that forms a second-order maximum? I used the equation [(1/d)sin(90)]/m = wavelength: [(1/0.93m)(1)] /2 = 0.5376m. To convert to nm I multiplied by

29. ## science

Two charges repel each other with a force of 10-5newton when they are 20cm apart. what is the force on each of them are i 3cm apart and ii when they are 100cm

30. ## PHYSICS

A rod 14.0 cm long is uniformly charged and has a total charge of -20.0 µC. Determine the magnitude and direction of the electric field along the axis of the rod at a point 36.0 cm from its center. N/C

31. ## Ronit

What is the current through a wire if 240 coulombs of charge pass through the wire in 2.0 minutes?

32. ## Paul

Determien the mass of the Sun using the known value for the period of the Earth and its distance from the Sun. I do not remeber how to do this F = ma = Fg = GmM/r^2 Period of earth 3.16 E 7 s radius earth to moon = 1.5 E 11 m

33. ## Physics

Unpolarised light of intensity 4.0Wm^−2 is incident on a polariser placed at 15∘ to the vertical. State the intensity of the transmitted light. I've tried 4 x cos(15)^2 = 3.732050808, but it says "Unpolarised light is a random mix of polarisations, so

34. ## physics

Scientists want to place a 3100 kg satellite in orbit around Mars. They plan to have the satellite orbit a distance equal to 1.9 times the radius of Mars above the surface of the planet. Here is some information that will help solve this problem: mmars =

35. ## physics

If A=4i+3j-2k, B=8i+6j-4k then the angle would be?

36. ## luma

A rock weighs 100 N in air and has a volume of 0.00312 m^3. What is its apparent weight when submerged in water? The acceleration of gravity is 9.8 m/s^2. Answer in units of N.

37. ## physics

Assume a cyclist of weight mg can exert a force on the pedals equal to 0.90 mg on the average. If the pedals rotate in a circle of radius 18 cm, the wheels have a radius of 34 cm, and the front and back sprockets on which the chain runs have 42 and 19

38. ## physics

find the resistance of 134m of No.20 copper wire at 20 degrees C (p=1.72x10^-6Ohom cm , A= 2.07x10^-2 cm ^2)

39. ## college physics

Two protons in a molecule are 3.80 multiplied by 10-10 m apart. Find the electrical force exerted by one proton on the other. Magnitude N (b) State how the magnitude of this force compares with the magnitude of the gravitational force exerted by one proton

40. ## k

Two wires parallel to each other and separated by a distance d carry different currents; they exert a force with magnitude F on each other. (a) The wires carry current in opposite directions. If the current carried by both wires is divided by five and the

41. ## Physics

A boxer punches a 50 Kg bag. Just as his fist hits the bag, it travels at a speed of 7 m/s. As a result of hitting the bag, his hand comes to a complete stop. Assuming that the moving part of his hand weigh 5 Kg, calculate the rebound velocity and kinetic

42. ## electric fields *easy

A charged particle is at the origin of coordinates. The particle produces an electric field of 4 kN/C at the point with position vector 36 cm. At what location does the field have the value 1 kN/C? Ans: 72 cm Could someone please explain to me what

43. ## Physics

The inner conductor of a coaxial cable has a radius of 0.900 mm, and the outer conductor's inside radius is 5.00 mm. The space between the conductors is filled with polyethylene, which has a dielectric constant of 2.30 and a dielectric strength of 18E6

I'm confused and am hoping someone could help me understand energy can neither be created nor destroyed... great... so in physics classes we can set up problems and stuff were KEo + PEo = KE + PE Energy intial equals energy final sense energy is conserved

45. ## physics

please check my answer An electron moves north at a velocity of 9.8 * 10^4 m/s and has a magnetic force of 5.6 * 10^-18 N west exerted on it. If the magnetic field points upward, what is the magnitude of the magnetic field? F=BqV F= 5.6 * 10^-18N q= 16 *

46. ## physics

What effect will be produced on a capacitor if the separation between the plates is increased? a. it will increase the charge b. it will decrease the charge c. it will increase the capacitance d. it will decrease the capacitance D A 0.25 uF capacitor is

47. ## physics

please check: A battery converts what type of energy into electrical energy? a. mechanical b. nuclear c. solar d. chemical D When a parallel-plate capacitor is connected to a battery:a____ is stored on one plate, and a ___ is stored on the other a.

48. ## physics

according to Lenz's law, the magnetic field of an induced current in a conductor will a. enhance the applied field b. heat the conductor c. increase the potential difference d. oppose a change in the applied magnetic field i think D

49. ## physics

If atmospheric refraction did not occur, how would the apparent time of sunrise and sunset be changed? a. both would be later b. both would be earlier c. sunrise would be later, and sunset would be earlier d. sunrise would be earlier, and sunset would be

50. ## physics

how would i go about solving this problem? what formula shoud i use? can you please show me in steps how to do this, thanks a lot: The critical angle of refraction for calcite is 68.4degrees when it forms a boundary with water. Use this information to

51. ## Physics

A box slides down a 30.0 degree ramp with an acceleration of 1.20 m/s^s Determine the coefficent of kinetic friction between the box and the ramp How on earth do I do this with only this amount of information???

52. ## Physics

The diagram below depicts three different circuits that light a bulb. The batteries are identical 1.5 V cells, and the light bulbs are identical. 1. Has 1 battery, 1 lightbulb in circuit 2. Has 2 battery, 1 lightbulb in circuit 3. Has 3 battery, 1

53. ## algebra

A schematic of a simple electrical circuit consisting of a resistor and an inductor is shown in the figure. The current I at time t is given by the formula I = 25e^(−Rt/L), where R is the resistance and L is the inductance. Solve this equation for t

54. ## Physics

A flat 100kg rock slides down a smooth rocky hill. It started from rest. The hill is 100m long and 50m high. The friction force between the rock and the ground is 150N. Use g=10m/s². Calculate the speed of the rock at the bottom of the hill

55. ## physics

mmars = 6.4191 x 1023 kg rmars = 3.397 x 106 m G = 6.67428 x 10-11 N-m2/kg2 3100 kg 1.9 times radius of mars What speed should the satellite have to be in a perfectly circular orbit? the force of attraction between mars and satellite is 1348

56. ## Physics

A black wood stove with surface area 4.6 m^2 is made from cast iron 4.0 mm thick. The interior wall of the stove is at 650 C, while the exterior is at 647 C. Part A What is the rate of heat conduction through the stove wall? Part B What is the rate of heat

57. ## Science

Two forces acting in the opposite direction have a resultant of 10N. If they act at the right angles to each other the resultant is 50N .the magnitude of the forces are

58. ## Science

Two forces have magnitude in the ratio 3:5 and the angle between their directions is 60Â°. If their resultant is 35N their magnitude are

59. ## Physics

during a race,a dragster is 200 meters from the finish line when something goes wrong and its stops accelerating.it travels at a constant velocity of45 meters per second for 3seconds to try to finish the race.How far from the finish line is the dragster

60. ## SIERRA

a fullback having a mass of 9.0x10^1 kg is running at 4.5 m/s [E]. He is hit by a linebacker and 1.2 s later is moving backwards at 1.5 m/s [W].Find: a) the impulse imparted to the fullback B) the average force exerted on the fullback by the linebacker my

61. ## PHYSICS

The gravitational forces of the Earth and the Moon are attractive, so there must be a point on a line joining their centers where the gravitational forces on an object cancel. How far is this distance from the Earth's center?

62. ## tsion

Determine whether each of the following statements is true or false. A concave mirror never forms an enlarged real image of a real object. >true A virtual image formed by a concave mirror is always smaller than the real object. >false A reduced image

63. ## n. i. o. s physics

How would you design a black body?

64. ## Physics

a 15-kg box is resting on a hill forming an angle with the horizontal. The coefficient of static friction for the box on the surface is 0.45. calculate the maximum angle of the incline just before the box starts to move

65. ## physics

We are standing at a distance d=15 m away from a house. The house wall is h=6 m high and the roof has an inclination angle β=30 ∘. We throw a stone with initial speed v0=20 m/s at an angle α= 35 ∘. The gravitational acceleration is g=10 m/s2. (See

66. ## PHYSICS

We are standing at a distance d=15 m away from a house. The house wall is h=6 m high and the roof has an inclination angle β=30 ∘. We throw a stone with initial speed v0=20 m/s at an angle α= 35 ∘. The gravitational acceleration is g=10 m/s2. (See

67. ## PHYSICS

A rod 14.0 cm long is uniformly charged and has a total charge of -20.0 µC. Determine the magnitude and direction of the electric field along the axis of the rod at a point 36.0 cm from its center. N/C

68. ## science

a machine gun can fire 20 bullet persecond if speed of bullet is 100m/s and if each bullet weight 100grams calcuate force required to hold the gun in its position

69. ## emily

What is the potential halfway between two point charges spaced 1 mm apart if q1=10 micro culumbs and q2= -5 micro culumbs

70. ## victor.M

What is the resulting temperature when a 150g cube of ice at zero degrees is added to 200g of water in a aluminium cup at 30 degrees

71. ## physics

The electric potential in a certain region is V = a x2 + b x + c, where a = 15 V/m2, b = −13 V/m, and c = 67 V. 1)Determine the electric field at x = 4 m. 2)Determine the position where the electric field is zero.

72. ## Physics

(b)A coin is placed 20 cm from the axis of a rotating turntable of variable speed. This speed is gradually increased and the coin remains fixed on the turntable until a rate of 36 rpm is reached. At this point, the coin slides off. What is the coefficient

73. ## physics

A man (weighing 915 N) stands on a long railroad flatcar (weighing 2720 N) as it rolls at 18.5 m/s in the positive direction of an x axis, with negligible friction. Then the man runs along the flatcar in the negative x direction at 55.00 m/s relative to

74. ## physics egg drop

What is the best idea for an egg drop project. it has to survive a 5 meter drope without craking or breaking open.(grade A egg wich is a bog egg). The desinge or idea has to be able to be opened and have the egg in hand within 10 sec, so packing it into

75. ## Physics

momentum equals = mass (velocity) yet for problems I end up using this P = m (delta v) what allows us to simply put the delta infront of the v to find the momentum?

76. ## Physics

A small block of mass m rests on the sloping side of a triangular block of mass M which itself rests on a horizontal table. Assuming all surfaces are frictionless, determine the magnitude of the force ->F that must be applied to M so that m remains in a

77. ## physics

A rope of negligible mass passes over a puley of a negligible mass attached to the ceiling. One end of the rope is held by stdent A of mass 70 kg who is at rest on the floor. The opposite end of the rope is held by student B of mass 60 kg who is suspended

78. ## physics

thanks for the help earlier just got a question I'm taking AP Physics B this year does that mean next year I would Take AP Physics C??? I don't know if the material in C convers the same material plus the additional calculus material or what??? Could I

79. ## Tj

a wire has a resistance of 10 ohms. The length of the wire is doubled, and its radius is also doubled. What is the new resistance?

80. ## Physics

Ok I guess the reason why I do not know how to do this problem is because I can not draw the proper free-body diagram... Three blocks on a frictionless horizontal surface are in contact with each other as shown in Fig. 4-5. A force F is applied to block 1

81. ## physics

I'm given a spring that has a mass of 100 g and a constant of 22 N/m with an A of 5 cm I belive the A is amplitude and I'm asked for the Total Energy which i don't know how to do the max velocity also have no idea how to do and the max force which i don't

82. ## mary

The question is: a horizontal force of magnitude 22.0 N is applied to a 2.86 kg book as the book slides a distance d = 0.73 m up a frictionless ramp at angle θ = 30°. The book begins with zero kinetic energy. What is its speed at the end of the

83. ## Physics

Hello can some one show and exlpain to me the derivation of this formula? V = (Ft(mL^-1)^-1)^(2^-1) or simply V = sqrt (F/(m/L)) were V = the veloctiy of a piece of string Ft = the force of tension m = mass L = length Thank you!

84. ## physics

please check: Two point charges, initially 1 cm apart, are moved to a distance of 3 cm apart. By what factor do the resulting electric and gravitational forces between them change? a. 9 b. 3 c. 1/3 d. 1/9 D Two positive charges, each of magnitude q, are on

85. ## physics

A concave mirror forms a real image at 17.0 cm from the mirror surface along the principal axis. If the corresponding object is at ta distance of 36.0 cm, what isi the mirror's focal length? let u be the object distance let v be the image distance v=17 cm

86. ## physics

please check these 3: if the batteries in a portable CD player provide a terminal voltage of 12 V, what is the potential difference across the entire CD player? a. 3.0 V b. 4.0 V c. 6.0 V d. 12 V D two resistors having the same resistance value are wired

87. ## physics

A 5.0 kg bucket of water is raised form a well by a rope. If the upward acceleratiopn of the bucket is 3.0 m/s^2 find the force exerted by the rope on the bucket of water what exactly do i do here? 3.0 m/s^2 upward? is this the Fn? I have no idea how to do

88. ## Physics

Each battery is a 1.5 V cell. If the resistance of the bulb in circuit 3 is 1 ohm (Ω), what is the current passing through the light bulb in circuit 3?

89. ## Physics

Each battery is a 1.5 V cell. If the current in circuit 2 is 3 amperes (3 A), what is the voltage drop across the light bulb for circuit 2?

90. ## Physics

Ohm's Law, ΔV = I • R, can be rewritten several ways. Which of the following is an incorrect way to rewrite Ohm's Law? I = ΔV / R R = ΔV / I I / ΔV = R 1 / R= I / ΔV

91. ## Physics

Ohm's Law, ΔV = I • R, can be rewritten several ways. Which of the following is an incorrect way to rewrite Ohm's Law? I = ΔV / R R = ΔV / I I / ΔV = R 1 / R= I / ΔV

92. ## physics

Ohm's Law, ΔV = I • R, can be rewritten several ways. Which of the following is an incorrect way to rewrite Ohm's Law? I = ΔV / R R = ΔV / I I / ΔV = R 1 / R= I / ΔV

93. ## physics

We have used analogies with Newton's Laws to help us understand the behavior of electricity. Which of the following is the best analogy for understanding electrical resistance? Electrical resistance is like the angle on an inclined plane. The steeper the

94. ## physics

Ohm's Law, ΔV = I • R, can be rewritten several ways. Which of the following is an incorrect way to rewrite Ohm's Law? I = ΔV / R R = ΔV / I I / ΔV = R 1 / R= I / ΔV

95. ## physics

calculate the geostrophic wind velocity: - coriolis parameter is: 1x10^-4 s^-1 = 0.0001s^-1 - height gradient on the 500hPa surface is 0.8m/km

96. ## physics

air parcel A has an air temperature of 5℃ and an absolute humidity of 5g/m^-3. What is its relative humidity and dew point temperature? Assume the air temperature is 1000hPa.

97. ## physics

Modern gasoline engines have a maximum thermal efficiency of about 20% to 35% when used to drive a car. Although the gasoline engine can be up to around 40% efficient (thermal efficiency), there is friction heat loss all along the way (drive train), such

98. ## Physics

A cube of solid aluminium has a volume of 1.0m^3 at 20°C. What temperature change is required to produce a 100cm^3 increase to the volume of the cube

99. ## Physics

What Is The Equvalent Resistance Of Two Resistor Are 2and3ohm connected in paralle each resistor