Monday

August 29, 2016
**Physics. **

An electron in a hydrogen atom is revolving around the proton in a orbit of radius r and velocity v .find the current.
*Sunday, July 31, 2016 by Sagnik *

**Physics**

For a given velocity of projection from a point on a inclined plane , the maximum range down the plane is three times the maximum range up the incline. Then find the angle of inclination of the inclined plane.
*Saturday, July 30, 2016 by ADITYA BABAR *

**Physics**

What is physics
*Saturday, July 30, 2016 by Val*

**Physics **

A sled has 300 kg m/s of momentum at point A. At point B the momentum is 375 kg m/s after 2 sec. What force was applied to the sled?
*Saturday, July 30, 2016 by BT*

**Physics **

A 75 kg individual runs a 5 m/s and jumps onto a stationary 40 kg wagon. What is the speed of the wagon and individual?
*Saturday, July 30, 2016 by BT*

**Physics **

Emma is working in a shoe test lab measuring the coefficient of friction for tennis shoes on a variety of surfaces. The shoes are pushed against the surface with a force of 400 N, and a sample of the surface material is then pulled out from under the shoe by a machine. The ...
*Saturday, July 30, 2016 by BT*

**Physics **

Emma is working in a shoe test lab measuring the coefficient of friction for tennis shoes on a variety of surfaces. The shoes are pushed against the surface with a force of 400 N, and a sample of the surface material is then pulled out from under the shoe by a machine. The ...
*Saturday, July 30, 2016 by BT*

**statistics**

in a certain college 33% of the physics majors belong to ethnic minorities. if 8 students are selected at random from the physics majors what is the probability that more than 5 belong to an ethnic minority
*Saturday, July 30, 2016 by bernie*

**physics**

three equal charges each of 2.0×10^-6 are fixed at three corner of an equilateral triangle of side 5cm .find the coulomb force experience due to other two charges
*Friday, July 29, 2016 by jelil*

**Physics**

If a man walks 4 km east and then 5 km south. How far is he from the point where he started?
*Friday, July 29, 2016 by Cathy*

**Physics**

A ladder 9 meters long is place a wall t base 2 metera away. What is the height reach by the ladder?
*Friday, July 29, 2016 by Cathy*

**physics**

a rock is dropped from a height of 20m above the ground when it hits the ground it leaves a hole 10cm deep with what speed does the rock hit the ground, and what is the magnitude of the rock's deceleration after it hits the ground
*Thursday, July 28, 2016 by kevin*

**physics**

find the energy of an x-ray photon which can impact a maximum energy of 50 kev to an electron
*Thursday, July 28, 2016 by priyanka*

**Physics**

(a) A narrow beam of light containing yellow (580 nm) and green (550 nm) wavelengths goes from polystyrene to air, striking the surface at a 30.0º incident angle. What is the angle between the colors when they emerge? (b) How far would they have to travel to be separated ...
*Wednesday, July 27, 2016 by Elizabeth*

**hard core physics **

A car is at motion.It horns an hears the echo of the sound after 6 sec.find the speed of the car.
*Wednesday, July 27, 2016 by j*

**Physics**

A hollow sphere starts from rest and rolls down a hill without sliding. At the bottom of the hill, it has a linear velocity of 5 m/s. What was the height of the hill the sphere rolled down (in meters)?
*Wednesday, July 27, 2016 by Rebecca*

**Physics **

A body of volume hundred centimetre cube is immersed completely in water contained in a jar containing water. the weight of the jar and the water before immersion was 700 grams. After immersion weight of the jar and the water will be
*Wednesday, July 27, 2016 by Vidhi*

**Physics **

A body of volume hundred centimetre cube is completely immersed in a jar containing water. The weight of the jar and the water before immersion was 700. After immersion weight of jar and water will be
*Wednesday, July 27, 2016 by Vidhi*

**physics**

a sky diver jumps out of a plane that is 3000m above ground with an initial upward speed of 6m/s she free falls for 20s (assume there is no wind at this time)before pulling the cord to activate the parachute she then falls to the ground at a constant downward speed of 5m/s, ...
*Wednesday, July 27, 2016 by gary*

**Physics **

What is the change in the volume of 1.0 L kerosene, when it is subjected to an extra pressure of 2.0 ×100000 N/m^2 if the density of the kerosene =800kg m^-3 and speed of sound in kerosene is 1300ms^-1
*Wednesday, July 27, 2016 by Vidhi*

**physics**

a person in a hot air balloon ascending vertically at a constant rate of 12m/s drops a rock over the side when the balloon is 40 m above the ground, what is the velocity of the rock just before it hits the ground, and how long will it take the rock to reach the ground
*Wednesday, July 27, 2016 by gary*

**Physics **

A cubical block of steel of side 'a ' and density 'p'floats on mercury of density with a part of it being submerged. The height of the block above the Mercury level is given by
*Wednesday, July 27, 2016 by Vidhi*

**science(physics)**

A bullet of mass 100g moving with20m/sec .Strikes a wooden plank and peretrates up to 20cm.Calculate the resistance offered by the wooden plank.
*Wednesday, July 27, 2016 by Raj*

**Science**

What is physics
*Wednesday, July 27, 2016 by Yashesh*

**Physics**

Considering a mass-spring system aligned horizontally moving at a velocity v. a) How will the velocity of the mass change if amplitude is doubled. b) How will the velocity of the mass change if the spring constant is quartered? I know the answer to the first one is that it ...
*Wednesday, July 27, 2016 by Lost*

**physics**

a person uses a slingshot to launch a rock upward with a velocity of 30m/s how long does it take to reach a height of 20m what maximum height does the rock reach, what is the velocity of the rock at this height, what is the velocity of the rock just before it lands
*Tuesday, July 26, 2016 by kyle*

**physics**

a driver starting from rest accelerates at a rate of 1.5m/s^2 for 20s until reaching a certain speed she then continues driving at this constant speed for an additional 20s what maximum speed does the driver attain what total distance does the driver cover during the 40s that ...
*Tuesday, July 26, 2016 by kyle*

**physics**

an arrow is shot vertically upward after 2s it is at a height of 36m although this is not necessarily the highest point with what velocity was the arrow shot what is the maximum height reached by the arrow how long is the arrow in flight altogether
*Tuesday, July 26, 2016 by craig*

**physics**

the takeoff speed for a large airplane is 180 mi/hr(roughly 80m/s0 the plane is capable of accelerating at a rate of 4m/s^2 assume that the plane starts at rest determine the minimum runway length required for this plane to safely take off a smaller airplane requires a takeoff...
*Tuesday, July 26, 2016 by craig*

**physics**

A stone is projected vertically upwards with a speed of 30ms from the top of a tower of height 50m. Neglecting air resistance determine the maximum height it reached from the ground.[g=10ms^2]
*Tuesday, July 26, 2016 by josh*

**physics**

the mass of a proton is 1836 times the mass of an electron a)a proton is traveling at speed v. at what speed (in terms of v) would an electron have the same kinetic energy as the proton? b) an electron has kinetic energy K. if a proton has the sane speed as the electron. what ...
*Tuesday, July 26, 2016 by hey*

**physics**

A car accelerates from rest at 1.0 m/s^2 for 20s along a straight roa, it then moves at a constant speed for half an hour, it then deccelerates uniformly to a stop in 30s. Find the total distance covered by the car.
*Tuesday, July 26, 2016 by sophia*

**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 after 3 seconds?
*Tuesday, July 26, 2016 by Physics*

**Physics **

A body accelerates uniformly from rest and covers a distance of 180m in 6s. Calculate the magnitude of its acceleration. . solution S=ut+1/2at^2 180=0x6+1/2xax6^2 180=0+a/2x6^2 180-0=36a/2 180=36a/2 180x2=36a 360=36a 360/36=36a/36 10ms^-2=a acceleration is 10ms^-2
*Tuesday, July 26, 2016 by Josh*

**physics**

an arrow is shot vertically upward 2 seconds later it is at a height of 42m (this may not be necesarily its highest point)with what velocity was the arrow shot, how long is the arrow in flight altogether
*Monday, July 25, 2016 by casey*

**physics **

a rock is dropped from a height of 20m above the ground when it hits the ground it leaves a hole 10cm deep. With what speed does the rock hit the ground, what is the magnitude of the rock's deceleration after it hits the ground
*Monday, July 25, 2016 by steve*

**physics**

a train moving at 35m/s slows down to 20 m/s over the course of 1 minute what distance does the train cover during this time, what is the trains acceleration during this time, if the train continued to slow down with the same acceleration how much more time would it take to ...
*Monday, July 25, 2016 by steve*

**physics**

a woman drives at a speed of 20m/s for part of a trip and at a speed of 30m/s for the rest of the trip if she spends 10 minutes driving at each speed determine her average speed for the full trip. If instead she drives 10 kilometers at each speed determine her average speed ...
*Monday, July 25, 2016 by steve*

**Physics**

There is an outcropping of ice with a large drop to a slope below. A 100kg piece of ice breaks off with a 60kg person on top of it, and falls o the slope below. The piece of ice slides down the slope to the bottom and onto a horizontal portion. It slides to a stop at a ...
*Monday, July 25, 2016 by Barry *

**Physics**

Calculate the λSWL for molybdenum, when the accelerating potential is 15 kV
*Monday, July 25, 2016 by Sowmi*

**college physics**

A student observes 30 waves traveling down a string in a lab experiment. It takes 10 seconds for the waves to all go by. What is the frequency of the waves (in Hz)?
*Monday, July 25, 2016 by Taylor*

**College physics**

Please help me... I have no idea where to begin...A tone of 4000 Hz is being played on a tuning fork. You run toward the tuning fork at 5 m/s. What frequency do you hear? Take the speed of sound to be 343 m/s.
*Monday, July 25, 2016 by Taylor*

**Physics**

A projectile has initially the same horizontal velocity as it would acquire if it had moved from rest with uniform acceleration of 3m/s² for 0.5 minute. If the maximum height reached by it is 80m then the angle of projection is[g=10m/s²]
*Monday, July 25, 2016 by Projectile *

**Physics**

how many coulombs must be on one object for it to be repelled with a force of 6.0 N by a second charge of 2.0uC at a distance of 1.0 m?
*Monday, July 25, 2016 by Kim*

**Physics**

Hello! can someone help me how to solve this problem in MATLAB? SHAFT SUBJECTED TO SINUSOIDAL DISTRIBUTED TORQUE Circular shaft AB has length 3L and is supported by a wall at A, where x=0, and free to rotate at B, where x=3L. A distributed torque per unit length T(x) = t_0*cos...
*Monday, July 25, 2016 by simonsay*

**physics**

a body is projected horizontally from height of 78.4 m with a velocity 10 m/s . its velocity after 3 sec
*Monday, July 25, 2016 by jayashree*

**PHYSICS**

a bus starts from rest and in 30s it reaches speed of 20m/s.then the speed remains steady for 15s and decreases steadily until it stops 5s later.what the distance covered from strat to finish.
*Sunday, July 24, 2016 by Muuka*

**Physics**

Jet of water striking series of radial flat vanes of the wheel is 200 mm and the velocity of the jet is 100 m/s. The velocity of the vanes is 46 m/s Calculate the force exerted on the series of vanes by the jet of water.
*Sunday, July 24, 2016 by Herman*

**physics**

three resistors of 2ohm, 3ohm and 4 ohm are connected in (a) series (b) parallel. find the equivalent resistance in each case
*Sunday, July 24, 2016 by ganga*

**Physics**

A cyclist moving on a corcular track of radius 40m completes half a revolution in 40 sec. Its average velocity is nearly
*Sunday, July 24, 2016 by Khilin*

**physics **

Calculate the momentum of a 100 kg object moving with velocity 10m/s
*Sunday, July 24, 2016 by rishabh *

**physics **

Calculate the momentum of a 100 kg object moving with velocity 10m/s
*Sunday, July 24, 2016 by rishabh *

**physics**

a pendulum swing with a speed of 1.5 m/s at its lowedt point. How high will it rise before it stops
*Sunday, July 24, 2016 by Anonymous*

**Physics **

At what positions is the speed of a simple harmonic oscillator half its maximum? That is, what values of x / X give v = ±vmax/2 , where X is the amplitude of the motion? Hello, I am so confused about this question. I am not really sure where to start. Thank you so much!
*Sunday, July 24, 2016 by Elizabeth*

**physics**

if an 80 meter high object placed 2 meter from a convex lens forms an image whose distance from the object is 2 meter; show with the aid of a diagram with appropriate scale the height of the image formed and confirm your answer using mirror law formula?
*Saturday, July 23, 2016 by amara*

**physics**

Ball A with a mass of 0.500 kg is moving east at a velocity of 0.800 m/s. It strikes ball B, also of mass 0.500 kg, which is stationary. Ball A glances off B at an angle of 40.0° north of its original path. Ball B is pushed along a path perpendicular to the final path of ...
*Saturday, July 23, 2016 by Matt*

**physics**

A 16.0-g bullet is shot into a wooden block at rest with mass 4550 g on a frictionless surface. The bullet strikes and is lodged in the block, causing is to slide at a speed of 1.20 m/s. Find the speed of the bullet (in m/s) before striking the block.
*Saturday, July 23, 2016 by Matt*

**physics**

A man walked 10 m north, then 5 m south. What distance did he walk? What is his final displacement?
*Saturday, July 23, 2016 by Face off*

**Physics**

A car takes up from west and accelerate uniformly at the rate of 4m/s square until it reaches a velocity of 10m/s. It then maintains this speed for 5secs and later decelerate at the rate of 2m/s square till it reaches its destination a) draw the velocity time graph of the ...
*Saturday, July 23, 2016 by Alif*

**Physics**

A weight suspended from an ideal spring oscillates up and down with a period T. If the amplitude of the oscillation is doubled, the period will be ? A. 1.5 T B. 2T C. T/2 D. T E. 4T
*Saturday, July 23, 2016 by SAGAR*

**Physics**

If you weigh 670 N on the earth, what would be your weight on the surface of a neutron star that has the same mass as our sun and a diameter of 15.0 km ? Take the mass of the sun to be ms = 1.99×1030 kg , the gravitational constant to be G = 6.67×10−11 N&#...
*Friday, July 22, 2016 by Ane*

**math**

In a class,30 students passed in math,20 passed in physics and 8 passed in both. How many students failed in both if the class has 45 students?
*Friday, July 22, 2016 by miki*

**PHYSICS **

on a partime job you are asked to bring a cylindrical iron rod of legnth 85.8 cm and diameter 2.85 cm from a storage room to a machinist. will you need a cart? (to answer calculate the weight of the rod.)
*Friday, July 22, 2016 by joshua*

**Physics**

Searches related to a stone is projected vertically upward with a speed of 14m/s from a tower 100m high. find the maximum height attained and the speed with which it strikes the ground
*Friday, July 22, 2016 by Anonymous*

**Physics,Mthe**

a body of mass is100an objet and volume is 10 .find the density
*Friday, July 22, 2016 by Patrick.da.prince*

**Physics**

I need to understand how to calculate the final 2 steps of this problem. Appreciate any help: For a circuit, consisting of a single battery and two light bulbs in parallel, what is the total resistance of the circuit if each light bulb has a resistance of 6.3 ohms? 1/Rt=1/R1+1...
*Thursday, July 21, 2016 by Anna*

**physics**

A child pulls a wagon with a force of 16 N by a handle making an angle of 20 degrees with the horizontal. If the wagon has a mass of 4.9 kg, to the nearest hundredth of a m/s2 what is the acceleration of the wagon?
*Thursday, July 21, 2016 by llama*

**Physics**

A particle moving along a line that passes through the origin has zero angular momentum about that origin true false
*Thursday, July 21, 2016 by SAGAR*

**Physics**

Center of mass of a body coincides with its center of gravity irrespective of its mass and size 1. True 2.False
*Thursday, July 21, 2016 by SAGAR*

**physics**

Is torque depends on the choice of origin
*Thursday, July 21, 2016 by SAGAR*

**Physics**

Two stars of mass M and 2M, a distance 3x apart rotates in circles about the common center mass "0" The gravitational force acting on the stars is KGM^2/x^2, what is value of K?
*Thursday, July 21, 2016 by SAGAR*

**PHYSICS**

A Car Of Mass 280kg Moving With A Velocity Of 30m/s
*Thursday, July 21, 2016 by value*

**physics**

You have a mass of 93 kg and are on a 56-degree slope hanging on to a cord with a breaking strength of 156 newtons. What must be the coefficient of static friction to 2 decimal places between you and the surface for you to be saved from the fire?
*Thursday, July 21, 2016 by baaaaaa*

**physics**

A skier traveling at 26.2 m/s encounters a 23 degree slope. (a)If you could ignore friction, to the nearest meter, how far up the hill does he go? (b)If the coefficient of kinetic friction in the previous problem was actually 0.11 and the slope 30 degrees, to the nearest meter...
*Thursday, July 21, 2016 by clache*

**physics**

if the big piston is 10 times of the sizes of the smaller piston to balance a 500Nload at the big piston (assume that the piston level are the same and the weight of the big piston can be ignored
*Thursday, July 21, 2016 by aloyy*

**Physics or Math**

Question: A Toyota car travelled at the rate of 70 km/hour leaves the house 2 hours after a Kia car has left and overtakes it in 5 hours. at what rate was Kia car travelling? what's the formula pls?
*Thursday, July 21, 2016 by John*

**Physics**

Question: A Toyota car travelled at the rate of 70 km/hour leaves the house 2 hours after a Kia car has left and overtakes it in 5 hours. at what rate was Kia car travelling? What's the formula?
*Thursday, July 21, 2016 by John*

**Physics**

Question: A Toyota car travelled at the rate of 70 km/hour leaves the house 2 hours after a Kia car has left and overtakes it in 5 hours. at what rate was Kia car travelling? What's the Formula pls? Thanks
*Thursday, July 21, 2016 by John*

**physics**

a police van moving on a highway with a speed of 30 kmph fired a bullet at a thief car speeding away in the same direction with a speed of 192kmph. if the muzzle speed of the bullet is 150 m per sec. the speed eith which the bullet hit the thief car is
*Thursday, July 21, 2016 by Ramakanth*

**Physics**

Question: A Toyota car travelled at the rate of 70 km/hour leaves the house 2 hours after a Kia car has left and overtakes it in 5 hours. at what rate was Kia car travelling?
*Thursday, July 21, 2016 by John*

**Math**

In a group of 500 students, 150 are studying physics, 220 are studying biology, and 100 are studying chemistry. At least 25 students are studying more than one of these sciences. What is the greatest possible number of these students that might NOT be studying any of these ...
*Wednesday, July 20, 2016 by Anonymous*

**Physics**

The answer "use the right-hand rule" isn't working for my brain. I'd really like to understand how to answer the following: You can make an electromagnet by wrapping wire around a wire and connecting the ends to a battery. If the battery is connected so that ...
*Wednesday, July 20, 2016 by Anna*

**physics**

Solar material has a density of about 3*10^-4kg/m^3,and the amount of matter released in a typical CME is around 1*10^15kg. Assuming mu solar material is mu_0, estimate the strength of the magnetic field at the suns surface during typical CME
*Wednesday, July 20, 2016 by unknown*

**physics**

An infinitely-long wire with resistivity 2.0*10^-8 ohm*m initially has 1.5 A of "conduction" current flowing through it. When the emf connected to the wire is turned off, this current stops in time of .6ns. Estimate the amount of displacement current created in the ...
*Wednesday, July 20, 2016 by Sally*

**Physics **

Two lead spheres at the same temperature have radii in the ratio 1:2.what is the ratio of their heat capacities
*Wednesday, July 20, 2016 by Vaishnavi *

**Physics**

Two resistors of 2.0 ohm and 3.0 ohm are connected a) in series b) in parallel, with a battery of 6.0V and negligible internal resistance. For each case draw a circuit diagram and calculate the current through the battery
*Wednesday, July 20, 2016 by Bella*

**physics**

A particle is moving along a circular path of radius r, when it makes half a rotation, what is the ratio between its displacement and distance? (a) 2π (b) π (c) π/2 (d) π/4
*Wednesday, July 20, 2016 by SAGAR*

**physics**

what is pin hole cemera
*Wednesday, July 20, 2016 by musa ezekiel*

**Physics**

In each cycle of its operation, a heat engine expels 2400 J of energy and performs 1800 J of mechanical work. (a) How much thermal energy must be added to the engine in each cycle? (b) Find the thermal efficiency of the engine.
*Wednesday, July 20, 2016 by Theaaaa03*

**Physics**

A second's pendulum is taken on the surface of moon where acceleration due to gravity is 1/6th of that of earth.Will the time period of pendulum remain same or increase or decrease?Give a reason.
*Wednesday, July 20, 2016 by Yashasvi*

**Physics**

ABC is an equilateral triangle of side 4.0 cm in a vacuum. There are point charges of 8.0C at A and B. Find (a) the potential, (b) the electric field at C.
*Wednesday, July 20, 2016 by Hezekiah*

**college physics**

Suppose an aeroplane is moving in the north direction and magnetic field is into the paper .Which part of aeroplane will b positively charged? A-its head B-its left wing C-its tail D- its right wing
*Wednesday, July 20, 2016 by Ghulam*

**physics**

a car moving through road what is the direction of force and surface of acting
*Wednesday, July 20, 2016 by Anonymous*

**Physics**

A paper ball is dropped from a height of 5 meters above the ground. It hits the ground traveling with a speed of 2 m/s. How much work did air resistance do on the paper ball? I dont know how to start this. PLease help
*Wednesday, July 20, 2016 by Jay*

**Physics**

Your ear is capable of differentiating sounds that arrive at the ear just 1.00 ms apart. What is the minimum distance between two speakers that produce sounds that arrive at noticeably different times on a day when the speed of sound is 340 m/s?
*Wednesday, July 20, 2016 by Elizabeth*

**Physics**

Horizontal electric power lines supported by vertical poles can carry large currents. Assume that Earth’s magnetic field runs parallel to the surface of the ground from south to north with a magnitude of 0.50××10^-4 Tesla and that the supporting poles are 38 m...
*Tuesday, July 19, 2016 by Mike*

**physics**

Moving a magnet inside a coil of wire will induce a voltage in the coil. How is the voltage in the coil increased? by moving the magnet inside the coil of wire more slowly by moving the magnet inside the coil of wire more rapidly by holding the magnet absolutely still by ...
*Tuesday, July 19, 2016 by Melissa Duckworth*

**Physics**

I don't understand what formula to use for this question: Points A and B each have an electric potential of +9 V. How much work is required to take 1 mC of charge from A to B? Thank you
*Tuesday, July 19, 2016 by Anna*

**Physics**

A bullet fired into a fixed target loses half of its initial velocity in penetrating 15cm. How much further it will penetrate before coming to rest?
*Tuesday, July 19, 2016 by Ramakanth*

**Physics **

if body having initial velocity of 10m/s moves with a uniform acceleration 10m/s then the final velocity when it covers a distance
*Tuesday, July 19, 2016 by Balaji*