Tuesday

June 30, 2015

June 30, 2015

**PHYSICS**

Find the mass of water that vaporizes when 4.04 kg of mercury at 210 °C is added to 0.498 kg of water at 81.6 °C. I am stuck on trying to figure out how to solve this. Please help!
*Wednesday, May 20, 2015 by KS*

**physics **

A skier stands on a 5 degree slope.if the cofficient of static friction is 0.1,does the skier start to slide down?
*Wednesday, May 20, 2015 by Anonymous*

**PHYSICS**

Find the mass of water that vaporizes when 4.04 kg of mercury at 210 °C is added to 0.498 kg of water at 81.6 °C.
*Wednesday, May 20, 2015 by KS*

**physics**

750km towards North West?
*Wednesday, May 20, 2015 by sana*

**PHYSICS**

A Goodyear blimp typically contains 5040 m3 of helium (He) at an absolute pressure of 1.10 x 105 Pa. The temperature of the helium is 282 K. What is the mass (in kg) of the helium in the blimp?
*Wednesday, May 20, 2015 by KS*

**PHYSICS**

The drawing shows an ideal gas confined to a cylinder by a massless piston that is attached to an ideal spring. Outside the cylinder is a vacuum. The cross-sectional area of the piston is A = 2.50 × 10-3 m2. The initial pressure, volume, and temperature of the gas are, ...
*Wednesday, May 20, 2015 by KS*

**PHYSICS**

A thermos contains 152 cm3 of coffee at 93.8 °C. To cool the coffee, you drop two 11.6-g ice cubes into the thermos. The ice cubes are initially at 0 °C and melt completely. What is the final temperature of the coffee in degrees Celsius? Treat the coffee as if it were ...
*Wednesday, May 20, 2015 by KS*

**physics**

What is current?
*Wednesday, May 20, 2015 by meenakshi*

**Physics**

On an inclined plane, how does a larger angle of inclination result in a faster speed? I tried working this out by myself using different values for the angle of incline and the same weight - which was just 100N. I found that the frictional force was equal to the force acting ...
*Tuesday, May 19, 2015 by Madeleine *

**physics**

1. The batteries in a digital alarm clock provide a terminal voltage of 9 V. What is the potential difference across the entire clock current? A. 4.5 V B. 18.0 V C. 9.0 V D. 6.0 V **C is my answer Am I correct? Thanks!!
*Tuesday, May 19, 2015 by nnd*

**Physics**

On an inclined plane, how does a larger angle of inclination result in a faster speed? I tried working this out by myself using different values for the angle of incline and the same weight - which was just 100N. I found that the frictional force was equal to the force acting ...
*Tuesday, May 19, 2015 by Madeleine *

**Physics**

A 5.0cm tall object is placed 16cm from a convex lens with a focal length of 8.4cm. What are the image height and orientation?
*Tuesday, May 19, 2015 by taylor*

**physics**

a convex mirror has a focal length of -10.0cm. what is the image position for an object that is placed l20.0cm from the mirror?
*Tuesday, May 19, 2015 by taylor*

**physics**

marco pushes a stalled car 20 meters with a constant force of 500N in 50 seconds. Calculate the average power marco required to move the car.
*Tuesday, May 19, 2015 by taylor*

**physics**

how much work is done lifting a 75 kg child 1.75m?
*Tuesday, May 19, 2015 by taylor*

**physics**

Two metallic spheres, each with a mass of 0.46 g are suspended as pendulums by light strings from a common point. They are given the same electric charge, and the two come to equilibrium when each string is at an angle of 5.2° with the vertical. If the string is 21.0 cm ...
*Monday, May 18, 2015 by samantha*

**physics**

a softball is thrown at a speed of 40 miles per hour in a course that makes an angle of 60 degrees with the positive x axis. what is the initial speed in the horizontal direction?
*Monday, May 18, 2015 by lee*

**PHYSICS**

Find the mass of water that vaporizes when 4.04 kg of mercury at 210 °C is added to 0.498 kg of water at 81.6 °C.
*Monday, May 18, 2015 by KS*

**Physics**

I can't figure out how to do this. design an experiment you could construct that might measure the amount of work it takes to change the volume of a gas in a piston. What materials would you use? What would you measure? What results would you expect? What if the results ...
*Monday, May 18, 2015 by Mark*

**Physics**

a ray of light is incident on an air-glass boundary at 30 degrees. The index of refraction of air is 1,and the index of refraction for the glass is 1.4. What is the angle of the reflected ray, and what is the angle of the refracted ray? Thanks in advance. Been stuck for three ...
*Monday, May 18, 2015 by Jennifer*

**physics**

A vessel contains 50 cc of mercury at 40ºc and heated to 70º c .how much amount of mercury will overflow.
*Monday, May 18, 2015 by mans*

**physics**

A boat heads across an East-West river flowing at 3 m/s [W]. The boat starts at the South End and travels at 6 m/s [N25W]. What is the velocity (including direction) of the boat with respect to the ground?
*Monday, May 18, 2015 by lorraine*

**Physics**

A pilot maintains a heading due west with an air speed of 240 km/h. After flying for 30 min, he finds himself over a town that he knows is 150 km west and 40 km south of his starting point. a) What is the wind velocity, in magnitude and direction? b) What heading should he now...
*Monday, May 18, 2015 by Jaime*

**Physics**

Two ropes are attached to a wagon, one horizontal to the west with a tension force of 40 N and the other east at an angle of 23° northward and a tension force of 50 N. Find the components of the net force on the cart
*Monday, May 18, 2015 by Ben*

**physics**

In a tug of war match, each side pulls with a force of 500N, but the rope does not move. How much work is done?
*Monday, May 18, 2015 by taylor*

**physics**

An 8kg block starts from rest from the top of a plane, inclined at 40o with respect to the horizontal, and slides down at a constant acceleration. If the coefficient of kinetic friction between the block the plane is 0.35 determine how far the block travels in 3s. 2013/
*Monday, May 18, 2015 by Anonymous*

**physics**

An 8kg block starts from rest from the top of a plane, inclined at 40o with respect to the horizontal, and slides down at a constant acceleration. If the coefficient of kinetic friction between the block the plane is 0.35 determine how far the block travels in 3s. 2013/
*Monday, May 18, 2015 by Anonymous*

**PHYSICS**

A BOAT WHICH HAS A SPEED IS 5 Km/Hr IN STILL WATER CROSSES A RIVER OF WIDTH 1 Km along the shortest possible path in 15 minutes. find velocity of the river water.
*Monday, May 18, 2015 by THIAGARAJAN*

**PHYSICS**

a river is flowing west to east at a speed of 5 m/ minutes .in what direction should a man on the south bank of the river capable of swimming of 10 m / minutes in still water should swim to cross the river 1. in short time 2.along short path
*Monday, May 18, 2015 by THIAGARAJAN*

**physics**

A body of mass 10 kg moving at a speed of 4 m/s collides with another body of mass 4 kg at rest. After collision, if the speed of the body of 4kg mass be 5 m/s, the speed of body of 10kg mass shall be?
*Sunday, May 17, 2015 by Satyabrata Saha*

**physics**

A body with mass 0.30 kg hangs by a spring with force constant 50.0 N/m. By what factor is the frequency of oscillation reduced if the oscillation is damped and reaches 1/e of its original amplitude in 100 oscillations?
*Sunday, May 17, 2015 by luh*

**physics**

An adventurous archaeologist crosses between two rock cliffs by slowly going hand over hand along a rope stretched between the cliffs. He stops to rest at the middle of the rope. The rope will break if the tension in it exceeds 25000N, and our hero’s mass is 90kg. (a) If...
*Sunday, May 17, 2015 by mega*

**physics**

A horizontal force of 50 N is required to pull an 8 kg block of aluminum at a uniform velocity across a horizontal wooden desk. What is the coefficient of kinetic friction?
*Sunday, May 17, 2015 by roem*

**Physics**

6) Two ice skaters suddenly push off against one another starting from a stationary position. The 45-kg skater acquires a speed of 0.375 m/s relative to the ice. What speed does the 60-kg skater acquire relative to the ice?
*Sunday, May 17, 2015 by Anonymous*

**Physics**

A body is projected with a velocity of 200m/s at an angle of 30 degrees above the horizontal. calculate the time taken to reach the maximum height, its velocity after 16s
*Sunday, May 17, 2015 by Osphens*

**Physics**

A car is going 18.3 m/s down a road. At time t=0s, a squirrel runs in front of the car 36 meters away. It takes the driver t=0.67s to slam on the brakes, but after that , the brakes offer a frictional force F(fr)=21000N. Her car masses at 1860 kg. a) How far does the car ...
*Sunday, May 17, 2015 by Catherine*

**Physics**

Two identical 2 ohm resistors are connected in parallel to a 1 ohm resistor in the circuit.the potential difference across the cell is 6 v and internal resistance is negligible.calculate the effect across the parallel combination
*Saturday, May 16, 2015 by Kholo*

**physics**

A net force of 1000 N is needed to accelerate a small 1200 kg car from 5 m/s to 8 m/s. Use the work-energy theorem to determine the net work done by the force.
*Saturday, May 16, 2015 by saeed*

**Physics**

A pendulum with a length of 1.25m has a period of 2.2s. What is the value of g?
*Friday, May 15, 2015 by Leah*

**Physics**

A projectile is fired with a velocity u at the entrance A to a horizontal tunnel of length L and height H. Determine the minimum value of u and the corresponding value of the angle θ for which the projectile will reach B at the other end of the tunnel without touching the...
*Friday, May 15, 2015 by Emon*

**physics**

a car rounds a curve with a radius of 45.0 m at a speed of 22.0 m/s. What is the centripetal acceleration of the car? please show work
*Friday, May 15, 2015 by taylor*

**Physics**

A tennis player makes a return at a speed of 18m/s and at a height of 3m to land in the court at a horizontal distance of 12m from her. What are the possible angles of projection of the wall
*Thursday, May 14, 2015 by Glory*

**Physics**

A satellite of the Earth has a mass of 1550 kg. It orbits Earth with a mean radius of orbit of 7.00 x 10^6 m. a) What is the gravitational potential energy of the satellite with respect to Earth?
*Thursday, May 14, 2015 by john*

**science(physics)**

The stream of a river is flowing with velocity 1 km/h.What should be the direction of a swimmer to cross the river straight if he can swim at the rate of 2 km/h in still water.
*Wednesday, May 13, 2015 by Anonymous*

**PHYSICS**

An ice chest at a beach party contains 12 cans of soda at 2.69 °C. Each can of soda has a mass of 0.35 kg and a specific heat capacity of 3800 J/(kg C°). Someone adds a 6.05-kg watermelon at 24.1 °C to the chest. The specific heat capacity of watermelon is nearly ...
*Wednesday, May 13, 2015 by KS*

**physics**

a car for half of its time at 80km/h and for rest half of time at 40 km/h. total distance covered is 60 km/h. what is the average speed of car find
*Wednesday, May 13, 2015 by Anonymous*

**physics**

In a police ballistics test, a 10.0-g bullet moving at 300 m/s is fired into a 1.00-kg block at rest. The bullet goes through the block almost instantaneously and emerges with 50.0% of its original speed. What is the speed of the block just after the bullet emerges
*Wednesday, May 13, 2015 by sam*

**physics**

A ball is projected upward at time t = 0.0 s, from a point on a roof 40 m above the ground. The ball rises, then falls and strikes the ground. The initial velocity of the ball is 15.4m/s. Consider all quantities as positive in the upward direction. The time when the ball ...
*Wednesday, May 13, 2015 by Ahmad*

**physics**

an eiastic cord can be stretched to its elastic limit by a load of 2N.if a 35cm length of the cord is extended 0.6cm by a force of 0.5N,what will be the length of the cord when the stretching force is 2.5cm.
*Wednesday, May 13, 2015 by Ayo*

**physics**

a 4.0-kg block is moving at 5.0 m/s along a horizontal frictionless surface toward an ideal spring that is attached to a wall. After the block collides with the spring, the spring is compressed a maximum distance of 0.68 m. ) Suppose now friction is present and k = 0....
*Wednesday, May 13, 2015 by sam*

**Physics **

+Q charge situate at center of equilateral triangle of side 'a'. If +q charge situate at each corner of triangle. Then find the direction and magnitude of resultant force.
*Wednesday, May 13, 2015 by Hussaina Bohra *

**Physics**

Hi! I am going to apply for a medical study admission test and where just wondering if you guys could help me to come up with the formula for solving this problem. I am not looking for a answer, just the mathematical formula to solve theese kind of questions. The question is ...
*Wednesday, May 13, 2015 by Marius*

**Physics**

Hi! i am going to apply for a medical study admission test and where just wondering if you guys could help me to come up with the formula for solving this problem. I am not looking for a answer, just the mathematical formula to solve theese kind of questions. The question is ...
*Wednesday, May 13, 2015 by Marius*

**physics**

Two metallic wires X and Y are connected to a series. wire X has length l and radius r . While Y has length 2 l and radius 2 r. find the ratio of total resistance of series combination and resistance wire X , if both the wires are of same material.
*Wednesday, May 13, 2015 by Thejaswini*

**Physics**

How much work is needed to move a -8.00 uC charge from the ground to a point whose potential is +75.0V ? I know -8.00 uc = -0.8 x 10^-6 then I used W = Fd but I can't seems to get right answer any hint is appreciated.
*Wednesday, May 13, 2015 by john*

**PHYSICS HELP!!**

A drop hammer of mass 120 kg falls 2.5 m onto a pile of mass 250 kg and drives it 70 mm into the ground. Calculate: a.The velocity with which the hammer strikes the pile (use the conservation of energy principle) b.The velocity immediately after the impact(use the conservation...
*Tuesday, May 12, 2015 by baz*

**PHYSICS HELP!!**

A motorised gearbox has a reduction ratio of 50:1. The power input to the gearbox is 5 kW at 1440 RPM. The gearbox efficiency is 85% under maximum load conditions. The output shaft of the gearbox is attached to a winch drum of pitch diameter 220 mm and is used to hoist a load...
*Tuesday, May 12, 2015 by baz*

**PHYSICS**

The force of repulsion between two identical negative charges is 3.95 N, when the charges are 35.0 cm apart. What is the magnitude of these charges?
*Tuesday, May 12, 2015 by Jonny*

**Electronics, Physics, Math**

5. A circuit is supplied with 30 VDC and contains three resistors connected in series. The value or R1 is 80Ω, the value of R2 is 1,000Ω , and the value of R3 is 4,200Ω . What is the voltage drop across R2? A. 5.68 V B. 2.14 V C. 4.61 V D. 6.82 V I keep coming ...
*Tuesday, May 12, 2015 by Vicki*

**Physics**

a hockey player makes a slap shot, exerting a constant force of 25.0N on the puck for .16 seconds. What is the magnitude of the impulse given to the puck
*Tuesday, May 12, 2015 by Morgan Hopp*

**Physics (optics)**

A ray of light traveling in air strikes the midpoint of one face of an equiangular glass prism (n = 1.74) at an angle of exactly 30.0â—¦ Trace the path of the light ray through the glass and find the angle of incidence of the ray at the bottom of the prism. ...
*Tuesday, May 12, 2015 by Dave*

**Physics**

If a small planet were discovered whose orbital period was twice that of Earth, how many times farther from the Sun would this planet be? The answer for this one is 1.6 earth radii, but I can't seems to get solution to find the answer. I would appreciate for any hint or help.
*Tuesday, May 12, 2015 by john*

**physics**

A skateboarder starts up a 1.30m high, 25.0° ramp at a speed of 6.70m/s. The skateboard wheels roll without friction. How far from the end of the ramp does the skateboarder touch down?
*Tuesday, May 12, 2015 by Anonymous*

**physics**

. A 1030-kg car going 3.4 m/s through a parking lot hits and sticks to the bumper of a stationary 1140-kg car. Find the speed of the joined cars immediately after the collision.
*Tuesday, May 12, 2015 by derrelk*

**physics**

a 22 kilo ohm resistor having a tolerance of 10% has failed. you have on hand five resistors, valued at 120, 220, 47, 33 and 120 kilo ohm respectively. what combination of these would you choose to connect in parallel to replace the failed component?
*Tuesday, May 12, 2015 by lou*

**Electronics, Physics **

In a circuit, a 10 Ω resistor is connected in series to a parallel group containing a 60 Ω resistor and a 5 Ω resistor. What is the total resistance in this circuit? A formula and explanation would be great!
*Tuesday, May 12, 2015 by Vicki*

**Physics**

What is the greatest safe speed, without skidding, that a 1700 kg car can have on a level curve of radius 215 meters if Mk=0.4 and Ms=.85? The correct answer is 42.3 but idk how to get it.
*Tuesday, May 12, 2015 by Victoria*

**Physics**

A 4 kg mass is held at rest against a vertical wall by force F, acting perpendicular to the wall. If Mk=.25 and Ms=.6, what is the minimum force that will keep the mass from moving?
*Tuesday, May 12, 2015 by Victoria*

**Physics**

What is the greatest safe speed, without skidding, that a 1700 kg car can have on a level curve of radius 215 meters if Mk=0.4 and Ms=.85? Answer=42.3 I tried using the equation mv^2/r=mg+Mk.
*Tuesday, May 12, 2015 by Victoria*

**Physics**

Does displacement always have to include angles and direction? For example a man travels 3 m (N) and 4m (E). Can you just put 5m for displacement or do you have to put the angle and direction? Explain why
*Monday, May 11, 2015 by Anonymous*

**Physics**

Does displacement always have to include angles and direction? For example a man travels 3 m (N) and 4m (E). Can you just put 5m for displacement or do you have to put the angle and direction? Explain why.
*Monday, May 11, 2015 by Anonymous*

**Physics **

A pendulum swings back and forth up to a maximum height of 1.52 m. Neglecting friction, what is the speed of the pendulum at the lowest position. a) 2.7 m/s b) 3.9 m/s c) 5.5 m/s d) 30. m/s I thought the answer would be 0 m/s because it wouldn't move at the lowest position...
*Monday, May 11, 2015 by Megan *

**PHYSICS HELP!!**

A drop hammer of mass 120 kg falls 2.5 m onto a pile of mass 250 kg and drives it 70 mm into the ground. Calculate: a.The velocity with which the hammer strikes the pile (use the conservation of energy principle) b.The velocity immediately after the impact(use the conservation...
*Monday, May 11, 2015 by baz*

**PHYSICS HELP!!**

A motorised gearbox has a reduction ratio of 50:1. The power input to the gearbox is 5 kW at 1440 RPM. The gearbox efficiency is 85% under maximum load conditions. The output shaft of the gearbox is attached to a winch drum of pitch diameter 220 mm and is used to hoist a load...
*Monday, May 11, 2015 by baz*

**physics **

an object of mass mf to fall a distance L, giving its energy to raise the bus of mass 0.50 kg. The focal point of the lab was the effect of an inclined plane (a ramp). What is the effect of a ramp on the force necessary to raise an object a vertical distance H? What is the ...
*Monday, May 11, 2015 by jake *

**physics questions**

1. The batteries in a digital alarm clock provide a terminal voltage of 9 V. What is the potential difference across the entire clock current? A. 4.5 V B. 18.0 V C. 9.0 V D. 6.0 V **C is my answer 2. Why does the earth have a magnetic declination? a. the earth's axis of ...
*Monday, May 11, 2015 by nnd*

**Physics **

Two resistors have resistances R1 and R2. When the resistors are connected in series to a 12.4-V battery, the current from the battery is 2.13 A. When the resistors are connected in parallel to the battery, the total current from the battery is 9.01 A. Determine R1 and R2. (...
*Monday, May 11, 2015 by Abigail*

**Physics**

two stars with equal mass of 4.0x10^15 kg are separated by a distance of 2 km. They are moving in circular obits around the middle between the two stars. What is the speed of the stars?
*Sunday, May 10, 2015 by Ricky*

**Physics**

A girl swings on a playground swing in such a way that at her highest point she is 4.1 m from the ground, while at her lowest point she is 0.8 m from the ground.What is her maximum speed? The acceleration due to gravity is 9.8 m/s2 .Answer in units of m/s.
*Sunday, May 10, 2015 by Anonymous*

** physics**

A bar of gold measures 0.15 m × 0.050 m × 0.050 m. How many gallons of water have the same mass as this bar?
*Sunday, May 10, 2015 by Anonymous*

**physics **

sixty complete waves passes a particular point in 4 seconds if the distance between 3 successive troughs of the wave is 15m calculate the speed of the wave
*Sunday, May 10, 2015 by eniola pelumi*

**physics**

sixty complete waves passes a particular point in 4 seconds if the distance between 3 successive troughs of the wave is 15m.calculate the speed of the wave
*Sunday, May 10, 2015 by Anonymous*

**Physics**

Consider a situation where immediately after birth, twins are separated. One continues to live on earth, while the other is whisked away in a space ship at 90% of the speed of light. After 65 years they are reunited. Will they look the same? Show proof of your answer through ...
*Sunday, May 10, 2015 by Brian*

**Physics**

Which of the following is correct for the two coherent light waves to produce zero light? The light waves should travel in perpendicular directions. The light waves are in phase with each other. The light waves are out of phase with each other. The light waves should pass ...
*Sunday, May 10, 2015 by Brian*

**Physics**

Laser light of wavelength 632nm is incident on a diffraction grating having 600 lines per mm. Determine the angular separation between the first and second order maxima
*Sunday, May 10, 2015 by Felicia*

**physics**

Two identical balls each of mass 0.1*10-3kg carry identical charges and are suspended by two non conducting threads of equal length. At equilibrium they position themselves. Calculate the charge on either ball.
*Saturday, May 9, 2015 by shivangi*

**Physics**

Calculate the tension in the string if a single pulley of velocity ratio 5 is used to raise a body of mass 200g through a distance of 4cm.
*Saturday, May 9, 2015 by John*

**Physics**

A car travels 300 m [N] along a road, then turns a corner and drives an additional 400 m [E]. Draw a vector diagram of the path travelled by the car, and then calculate the car's distance travelled and its displacement. The displacement is 500m and the distance is 1200m. ...
*Saturday, May 9, 2015 by Anonymous*

**physics**

If a small planet were discovered whose orbital period was twice that of Earth, how many times farther from the Sun would this planet be?
*Saturday, May 9, 2015 by Jon*

**Physics**

The speed of light is about 3.00 x 10 to the power of 5 km/s. It takes approx. 1.28 seconds for light reflected from the moon to reach Earth. What is the average distance from Earth to the moon? Thank you
*Friday, May 8, 2015 by Steph*

**Physics**

A heat engine is 20% efficient. If it loses 800 J to the cooling system and exhaust during each cycle, the work done by the engine is: 200 J 1000 J 800 J 20 J
*Friday, May 8, 2015 by Steve*

**Physics**

If ∆Q is the heat supplied to a gas so that the internal energy of the system increases by ∆U, then the work done ∆W by the gas is equal to: ∆Q – ∆U ∆Q + ∆U ∆Q x ∆U ∆U/∆Q
*Friday, May 8, 2015 by Gary*

**Physics**

How many kg of ice needs to be added to 1.31 kg of water at 64.9°C to cool the water to 14.9°C when the Latent heat of ice = 80 kcal/kg?
*Friday, May 8, 2015 by Steve*

**Physics**

You know there are 1,609 metres in a mile. The number of feet in a mile is 5,280. Use these equalities to answer hoe many centimetres equals once inch. Thank you.
*Friday, May 8, 2015 by Steph*

**Physics**

How far can a person run in 15minutes if he or she runs at an average of 16km/hr? Thank you
*Friday, May 8, 2015 by Steph*

**Physics**

The average speed of a car was 60m/s by the time it reached the finish line. The car moved in a straight line and travelled from the starting line to the finish line in 8.0 sec. How far was the finish line? d = v x t d = 60 x 8 = 480 metres. Thank you
*Friday, May 8, 2015 by Steph*

**Physics**

The space shuttle releases a space telescope into orbit around the earth. The telescope is traveling at a speed of 1700m/s in 25 seconds. What is the distance of the satellite? d = v x t d = 1700 x 25 = Is that the correct formula? Thank you.
*Friday, May 8, 2015 by Steph*

**physics**

a bullet fired with a speed of 150 m/sec from car whose velocity is 25/3 m/sec to car next to it whose velocity is 50 m/sec.what is velocity of bullet with respect to ground?
*Thursday, May 7, 2015 by vishal*

**Physics Electric Circuits **

3. A 15.0 ohm resistor is connected in series to a 120 V generator and two 10.0 ohm resistors that are connected in parallel to each other. b) What is the current through the 15.0 ohm resistor? c) What is the current through one of the 10.0 ohm resistors? b- I did 120 V/15.0 ...
*Thursday, May 7, 2015 by Bridget*

**physics**

A rock falls off the edge of a cliff and strikes the ground after 3.8 s. What is the height of the cliff? Assume air resistance is negligible
*Thursday, May 7, 2015 by angela*