Thursday

September 29, 2016
**Physics for **

A force has the dependence Fx(x) = -kx^4 on the displacement x, where the constant k = 20.3 N/m^4. How much work does it take to change the displacement, working against the force, from 0.730 m to 1.35 m?

*Saturday, December 19, 2015 by Khalid*

**Physics**

A gram molecule of a gas at 127°C expands isothermally until its volume is doubled. Find the amount of work done and heat absorbed.

*Saturday, December 19, 2015 by Ques*

**physics**

A rock is shot up vertically upward from the edge of the top of the building. The rock reaches its maximum height 2 s after being shot. Them, after barely missing the edge of the building as it falls downward, the rock strikes the ground 8 s after it was launched. Find (a) ...

*Friday, December 18, 2015 by Jake*

**physics**

Let's say you're driving in your car, approaching a red light on the Camp Hill Bypass. A black Porsche is stopped at the light in the right lane, but there's no-one in the left lane, so you pull into the left lane. You're traveling at 40 km/hr, and when you'...

*Friday, December 18, 2015 by Jake*

**physics**

What must be the radius of an unbanked (flat) curve so that a car can safely travel at a maximum speed of 39 m/s? The coefficient of static friction is 0.70.

*Friday, December 18, 2015 by EMILY*

**PHYSICS**

An object is initially moving in the positive direction of an x-axis with a speed of 2.7 m/s. If the constant acceleration of the object is -0.12 m/s2, what distance will it have traveled when it turns around?

*Friday, December 18, 2015 by rebecca*

**Physics**

A ski jumper glides down a 30.0 degrees slope for 80.0 ft before taking off from a negligibly short horizontal ramp. If the jumpers takeoff speed is 45.0 ft/s, what is the coefficient of kinetic friction between skis and slope?

*Friday, December 18, 2015 by Khalid*

**Art**

file:///C:/Users/Piccollo/Desktop/1190597-6192014-20424-PM-1750126416.jpg In this creation what important components are used to the greatest effect? A)color and space B)architectural design**** C)physics and mathematics D)innovation and creativity Am I right?

*Friday, December 18, 2015 by Animesawesome*

**Physics**

A father pulls his son, whos mass is 25 kg and who is sitting on a swing with ropes of length 3 meters, backward until the ropes make an angle of 33.6 degrees with respect to the vertical. He then releases his son from rest. What is the speed of the son at the bottom of the ...

*Friday, December 18, 2015 by Khalid*

**Physics**

A father pulls his son, whos mass is 25 kg and who is sitting on a swing with ropes of length 3 meters, backward until the ropes make an angle of 33.6 degrees with respect to the vertical. He then releases his son from rest. What is the speed of the son at the bottom of the ...

*Friday, December 18, 2015 by Khalid*

**Physics**

1)An alloy of copper zinc has a mass of 4.9kg.when suspended in water.0.98kg of water was displaced by it.calculate the mass of zinc in the alloy if 2.5 and 19.6 are the specific gravity of the zinc and copper respectively 2) A steel ball of diameter 0.2mm, falls with a ...

*Friday, December 18, 2015 by Skyboy*

**Physics**

A box of unknown mass is sliding with an initial speed vi = 5.40 m/s across a horizontal friction-less warehouse floor when it encounters a rough section of flooring d = 3.50 m long. The coefficient of kinetic friction between the rough section of flooring and the box is 0.100...

*Thursday, December 17, 2015 by Anonymous*

**Physics**

A person weighs 600 N on Earth. What is the person's mass?

*Thursday, December 17, 2015 by Val*

**Physics**

A father pulls his son, whos mass is 25 kg and who is sitting on a swing with ropes of length 3 meters, backward until the ropes make an angle of 33.6 degrees with respect to the vertical. He then releases his son from rest. What is the speed of the son at the bottom of the ...

*Thursday, December 17, 2015 by Khalid*

**physics**

If a steel cube is placed on a surface that is increasing in slope. At what angle will the cube start to move

*Thursday, December 17, 2015 by jake*

**Physics!**

A person is standing on a 10-m bridge above a road. He wants to jump from the bridge and land in the bed of a truck that is approaching him at 30 m/s. In order to clear the bridge railing, he has to jump upward initially with a speed of 5 m/s. How far away should the truck be ...

*Thursday, December 17, 2015 by Emma*

**Physics**

Two springs are set up on a table. The longer spring has a spring constant of 221 N/m and an initial length of 44.0cm. The shorter spring has a spring constant of 725 N/m and an initial length of 22.0cm. How far above the table is an 9.30kg ball when it reaches its equilibrium...

*Thursday, December 17, 2015 by john*

**PHYSICS**

FIND THE MASS OF A 200 n BABY ELEPHANT

*Thursday, December 17, 2015 by JESSICA*

**PHYSICS! Really Confused! Test Tmrw**

A person is standing on a 10-m bridge above a road. He wants to jump from the bridge and land in the bed of a truck that is approaching him at 30 m/s. In order to clear the bridge railing, he has to jump upward initially with a speed of 5 m/s. HOW FAR AWAY SHOULD THE TRUCK BE ...

*Thursday, December 17, 2015 by Emma*

**Physics**

Two springs are set up on a table. The longer spring has a spring constant of 221 N/m and an initial length of 44.0cm. The shorter spring has a spring constant of 725 N/m and an initial length of 22.0cm. How far above the table is an 9.30kg ball when it reaches its equilibrium...

*Thursday, December 17, 2015 by Anon*

**Physics**

mike is skiing downhill at a 25 degree angle. if his weight is 350N assuming there is no friction what is his acceleration

*Thursday, December 17, 2015 by Karissa*

**physics **

Charge Q1=6.0 nC is at (0.30 m, 0), charge Q2=−1.0 nC is at (0, 0.10 m), and charge Q3=5.0 nC is at (0, 0). What is the magnitude of the net electrostatic force on the 5.0-nC charge due to the other charges? What is the direction of the net electrostatic force on the 5.0...

*Thursday, December 17, 2015 by ira*

**Physics**

A golfer rides in a golf cart at an average speed of 3.93 m/s for 43.3 s. She then gets out of the cart and starts walking at an average speed of 1.13 m/s. For how long (in seconds) must she walk if her average speed for the entire trip, riding and walking, is 1.99 m/s? Can ...

*Thursday, December 17, 2015 by Josh*

**chemistry, physics**

What is the most important source of error in the calorimeter experiment? I know few, but I don't know what is the most important source of error. Stirring error the calorimeter is not properly insulated Calculation error Measurement error in volume and or weight

*Wednesday, December 16, 2015 by miyabi*

**chemistry, physics**

How would you be able to utilize a calorimeter to determine the specific heat of substance that has a lower density than water?

*Wednesday, December 16, 2015 by miyabi*

**chemistry, physics**

In the specific heat measurement does the sample have to be 100 C, or would a lower initial temperature do just aa well? I wrote down it doesn't matter, but i don't know why.

*Wednesday, December 16, 2015 by miyabi*

**physics.. **

This seems easy and yet i'm skeptical if these are actually supposed to be difficult.. It asks for a lot. It's seems repetitive.. 1. a falling stone takes .30 seconds to travel past a window 2.2m tall. From what height above the top of the window did the stone fall? 2...

*Wednesday, December 16, 2015 by Abby*

**chemistry, physics**

When measuring specific heat, why should your final temperature be the maximum temperature reached calorimeter?

*Wednesday, December 16, 2015 by miyabi*

**physics**

A 2.0 kg mass rests on a frictionless wedge that has an acceleration of 15 m/s2 to the right. The mass remains stationary relative to the wedge, moving neither higher nor lower. (a) What is the angle of inclination, θ, of the wedge, i.e., the angle between the inclined ...

*Wednesday, December 16, 2015 by Anonymous*

**Physics**

A golf ball is dropped from rest from a height of 8.30 m. It hits the pavement, then bounces back up, rising just 5.00 m before falling back down again. A boy then catches the ball when it is 1.10 m above the pavement. Ignoring air resistance, calculate the total amount of ...

*Wednesday, December 16, 2015 by Courtney*

**Physics**

A tourist being chased by an angry bear is running in a straight line toward his car at a speed of 6.04 m/s. The car is a distance d away. The bear is 28.8 m behind the tourist and running at 7.26 m/s. The tourist reaches the car safely. What is the maximum possible value for d?

*Wednesday, December 16, 2015 by Courtney*

**PHYSICS**

A golfer rides in a golf cart at an average speed of 3.93 m/s for 43.3 s. She then gets out of the cart and starts walking at an average speed of 1.13 m/s. For how long (in seconds) must she walk if her average speed for the entire trip, riding and walking, is 1.99 m/s?

*Wednesday, December 16, 2015 by James*

**PHYSICS**

A box is sliding up an incline that makes an angle of 21.8° with respect to the horizontal. The coefficient of kinetic friction between the box and the surface of the incline is 0.170. The initial speed of the box at the bottom of the incline is 3.48 m/s. How far does the ...

*Wednesday, December 16, 2015 by James*

**physics**

A golf ball is dropped from rest from a height of 8.30 m. It hits the pavement, then bounces back up, rising just 5.00 m before falling back down again. A boy then catches the ball when it is 1.10 m above the pavement. Ignoring air resistance, calculate the total amount of ...

*Wednesday, December 16, 2015 by chris*

**physics**

A model rocket blasts off from the ground, rising straight upward with a constant acceleration that has a magnitude of 90.3 m/s2 for 1.75 seconds, at which point its fuel abruptly runs out. Air resistance has no effect on its flight. What maximum altitude (above the ground) ...

*Wednesday, December 16, 2015 by chris*

**physics**

A golfer rides in a golf cart at an average speed of 3.93 m/s for 43.3 s. She then gets out of the cart and starts walking at an average speed of 1.13 m/s. For how long (in seconds) must she walk if her average speed for the entire trip, riding and walking, is 1.99 m/s?

*Wednesday, December 16, 2015 by chris*

**physics**

A projectile is launched from and returns to ground level, as the figure shows. There is no air resistance. The horizontal range of the projectile is measured to be R= 166 m, and the horizontal component of the launch velocity is v0x = 26.0 m/s. Find the vertical component v0y...

*Wednesday, December 16, 2015 by chris*

**physics**

Traveling at a speed of 16.5 m/s, the driver of an automobile suddenly locks the wheels by slamming on the brakes. The coefficient of kinetic friction between the tires and the road is 0.590. What is the speed of the automobile after 1.35 s have elapsed? Ignore the effects of...

*Wednesday, December 16, 2015 by chris*

**physics**

Traveling at a speed of 19.0 m/s, the driver of an automobile suddenly locks the wheels by slamming on the brakes. The coefficient of kinetic friction between the tires and the road is 0.660. What is the speed of the automobile after 1.31 s have elapsed? Ignore the effects of ...

*Wednesday, December 16, 2015 by trish*

**physics **

a radioactive sample has a decay rate R of 518 decay/min at time t=7 min and 156 decay/ min at time t=17 min. calculate the decay constant and the initial decay rate?

*Wednesday, December 16, 2015 by renaa *

**physics**

Chapter 02, Problem 62 A model rocket blasts off from the ground, rising straight upward with a constant acceleration that has a magnitude of 90.3 m/s2 for 1.75 seconds, at which point its fuel abruptly runs out. Air resistance has no effect on its flight. What maximum ...

*Wednesday, December 16, 2015 by trish*

**physics**

A golf ball is dropped from rest from a height of 8.30 m. It hits the pavement, then bounces back up, rising just 5.00 m before falling back down again. A boy then catches the ball when it is 1.10 m above the pavement. Ignoring air resistance, calculate the total amount of ...

*Wednesday, December 16, 2015 by trish*

**physics**

A golf ball is dropped from rest from a height of 8.30 m. It hits the pavement, then bounces back up, rising just 5.00 m before falling back down again. A boy then catches the ball when it is 1.10 m above the pavement. Ignoring air resistance, calculate the total amount of ...

*Wednesday, December 16, 2015 by trish*

**physics**

Consult Interactive Solution 2.22 before beginning this problem. A car is traveling along a straight road at a velocity of +38.8 m/s when its engine cuts out. For the next 2.01 seconds, the car slows down, and its average acceleration is . For the next 6.36 seconds, the car ...

*Wednesday, December 16, 2015 by trish*

**physics**

Chapter 02, Problem 09 A tourist being chased by an angry bear is running in a straight line toward his car at a speed of 6.04 m/s. The car is a distance d away. The bear is 28.8 m behind the tourist and running at 7.26 m/s. The tourist reaches the car safely. What is the ...

*Wednesday, December 16, 2015 by trish*

**physics**

A box is sliding up an incline that makes an angle of 21.8° with respect to the horizontal. The coefficient of kinetic friction between the box and the surface of the incline is 0.170. The initial speed of the box at the bottom of the incline is 3.48 m/s. How far does the ...

*Wednesday, December 16, 2015 by trish*

**physics**

Three deer, A, B, and C, are grazing in a field. Deer B is located 61.0 m from deer A at an angle of 54.1 ° north of west. Deer C is located 79.8 ° north of east relative to deer A. The distance between deer B and C is 98.1 m. What is the distance between deer A and C?

*Wednesday, December 16, 2015 by trish*

**physics**

A 15.7-g bullet is fired from a rifle. It takes 3.00 × 10-3 s for the bullet to travel the length of the barrel, and it exits the barrel with a speed of 779 m/s. Assuming that the acceleration of the bullet is constant, find the average net force exerted on the bullet.

*Wednesday, December 16, 2015 by trish*

**Physics Sound Waves**

A fire truck emitting a 450 Hz signal passes by a stationary detector. The difference in frequency measured by the detector is 58 Hz. If the speed of sound is 345 m/s, how fast is the fire truck moving? The answer should be 22 m/s but I don't even know where to start. ...

*Wednesday, December 16, 2015 by R*

**physics**

A box is sliding up an incline that makes an angle of 21.8° with respect to the horizontal. The coefficient of kinetic friction between the box and the surface of the incline is 0.170. The initial speed of the box at the bottom of the incline is 3.48 m/s. How far does the ...

*Wednesday, December 16, 2015 by trish*

**Physics**

Three people are pulling on a tree. The first person pulls with 16N at 64.0 degrees. The second person pulls with 15 N at 136 degrees. The 3rd person pulls with 12 N at 195 degrees. What is the magnitude and direction of the resultant force on the three?

*Wednesday, December 16, 2015 by Gtueyb*

**Physics **

Take the mass of the Earth to be 5.98 × 1024 kg. If the Earth’s gravitational force causes a falling 44 kg student to accelerate downward at 9.8 m/s2, determine the upward accelera- tion of the Earth during the student’s fall. Answer in units of m/s2.

*Wednesday, December 16, 2015 by Lily *

**Physics**

Why we have to know refractive index and can use this in normal life?

*Wednesday, December 16, 2015 by Akhter*

**Physics**

A tugboat pulls a ship with a constant horizontal force of 6000N and causes the ship to move through a harbor. The water exerts a constant drag force on the ship of 500N. How much work is done on the ship if it moves a distance of 4.0 km? Force is causing parallel displacement...

*Wednesday, December 16, 2015 by Felix*

**physics**

a car which weight is 1000N is travelling at 90kmn/hr and come to rest in a distance of 50m after applying the brakes. assume uniform acceleration, calculate how large its stopping force was exerted by the friction between the wheel and the road.

*Wednesday, December 16, 2015 by samuel*

**Physics **

An 8.0g bullet is fired into a 2.5 Kg block at rest at the edge of a friction-less table of height 1.0 m. The bullet remains in the block and after the impact the block lands (d) distance from the bottom of the table. Find the initial speed of the bullet. Now I do realize this...

*Tuesday, December 15, 2015 by Aziz*

**Physics**

Compute the initial upward acceleration of a rocket of mass 1.5 ✕ 104 kg if the initial upward force produced by its engine (the thrust) is 2.7 ✕ 105 N. Do not neglect the weight of the rocket. Pleas tell me the steps, I've tried getting the acceleration and ...

*Tuesday, December 15, 2015 by Will*

**physics**

An object of mass m attached to a spring of force constant k oscillates with simple harmonic motion. The maximum displacement from equilibrium is A and the total mechanical energy of the system is E. What is the object's velocity when its potential energy is 2/3E? the ...

*Tuesday, December 15, 2015 by anna*

**physics**

3. Only two forces act on an object. The magnitude of the first force is 25 N and it acts at an angle of +25° with the positive x-axis. The second force acts at angle of -73° with the positive x-axis. The acceleration of the object is parallel to the positive x-axis. ...

*Tuesday, December 15, 2015 by rebecca*

**Physics**

A spring with a force constant of 1.0 N/cm is compressed to a displacement of 10.0 cm. When released, it's energy is used to rotate a mass of 0.50 kg, secured by a spring, around in a circle with radius of 0.75 m, starting at the top of the circle. After 0.3 s has elapsed...

*Tuesday, December 15, 2015 by Laura*

**Physics**

A spring with a force constant of 1.0 N/cm is compressed to a displacement of 10.0 cm. When released, it's energy is used to rotate a mass of 0.50 kg, secured by a spring, around in a circle with radius of 0.75 m, starting at the top of the circle. After 0.3 s has elapsed...

*Tuesday, December 15, 2015 by Laura*

**physics**

a bullet of mass0.01 kg is fired into a sandbag of mass 0.49kg hanging from a tree. the sandbag with the bullet embedded into it, swings away at 10m/s. find momentum after

*Tuesday, December 15, 2015 by Sipara*

**Physics**

A gymnast on a high bar swings through two revolutions in a time of 1.90s. Find the angular velocity of the gymnast

*Tuesday, December 15, 2015 by Anonymous*

**Physics**

A child on a sled is sliding at a speed of 4m/s across level ice. if the total mass of the sled + child is 50kg and the sled has steel runners, how long will it take the sled to come to a halt? what force will be required to start it moving again? If this force continues to be...

*Tuesday, December 15, 2015 by Roisin*

**physics**

a place kicker kick a ball 36m from a goal .which is 3.05 m high.it leaves the ground 20 m/s at an angle 53 to the horizontal.how much the ball clear or fall short of clearing the bar

*Tuesday, December 15, 2015 by geof*

**PHYSICS**

To see how two traveling waves of the same frequency create a standing wave. Consider a traveling wave described by the formula y1(x,t)=Asin(kx−ωt). This function might represent the lateral displacement of a string, a local electric field, the position of the ...

*Tuesday, December 15, 2015 by SENDICA*

**physics**

A projectile is launched at ground level with an initial speed of 56.0 m/s at an angle of 35.0° above the horizontal. It strikes a target above the ground 2.90 seconds later. What are the x and y distances from where the projectile was launched to where it lands?

*Tuesday, December 15, 2015 by tjjjj*

**Physics**

A 56.5kg, 2.4m uniform ladder leans against a frictionless wall. A 95.5kg person is standing up 0.8m from the bottom of the ladder. The ladder makes an angle of 57 degrees with the horizontal. The coefficient of static friction between th eladder and the ground is 0.15. What ...

*Monday, December 14, 2015 by James *

**physics**

Practice Problem 13.9 Let's begin by looking at a flow problem in which the diameter of a pipe changes along the flow path. We will need to use both the continuity equation and Bernoulli's equation for this problem. Water enters a house through a pipe with an inside ...

*Monday, December 14, 2015 by lost*

**Physics**

A car at the Indianapolis-500 accelerates uniformly from the pit area, going from rest to 290 km/h in a semicircular arc with a radius of 200 m. Determine the tangential acceleration of the car when it is halfway through the turn, assuming constant tangential acceleration. ...

*Monday, December 14, 2015 by asher*

**Physics**

As part of a challenge lab, a student determines that a spring powered marble cannon will fire a 0.03kg marble to a maximum height of 0.8m when the cannon is set to the second medium firing position and fired vertically A. If setting the medium firing position requires that ...

*Monday, December 14, 2015 by V*

**Physics**

The spring in a spring loaded cannon has a spring constant of 470N/m. A 0.05kg ball bearing is loaded into the cannon and the spring is compressed 0.1m. What will be the velocity of the ball bearing the instant before it hits the ground if the cannon s fired horizontally off ...

*Monday, December 14, 2015 by V*

**Physics**

What is the minimum speed you would need to roll a lacrosse ball down a flat street for it to be able to roll over a speed bump with a height of 12 cm

*Monday, December 14, 2015 by V*

**Physics**

_________________________________________________________________ You find yourself on your bike at the top of Twin Peaks in San Francisco. You are facing a 600m descent. You and your bike weigh a combined 85 kg. 1. How much gravitational potential energy do you have ...

*Monday, December 14, 2015 by V*

**Physics**

Just before your mountain bike ride, you eat a 240 Calorie exercise bar. (You can find the conversion between food Calories and Joules in the People’s Physics chapter and several references online.) The carbon bonds in the food are broken down in your stomach, releasing ...

*Monday, December 14, 2015 by V*

**physics**

A 1.22 kg skateboard is coasting along the pavement at a speed of 5.84 m/s when a 1.20 kg cat drops from a tree vertically downward onto the skateboard. What is the speed of the skateboard-cat combination?

*Monday, December 14, 2015 by Jake*

**physics**

A ball is thrown directly upward at 19.6 m/s how much time passes before the ball reaches the top of its motion

*Monday, December 14, 2015 by a.a*

**physics**

A rock is dropped from the top of a tall bridge after 3 seconds how far has the rock fallen due to gravity

*Monday, December 14, 2015 by a.a*

**Physics**

A car and a truck starts from rest at the same instant, with the car initially at some distant behind the truck. The truck has a constant acceleration of 2.1 m/s^2, and the car at 3.4 m/s^2. The car overtakes the ruck after it has moved 40.0 m. a) how much time does it take ...

*Monday, December 14, 2015 by April Catubig*

**Physics Part A HELP!!**

4.) In coming to a stop, a car leaves skid marks 80m long on the highway. Assuming a DEceleration of 7.00 m/s^2 (m/s/s), estimate the speed of the car just before breaking. 6.) A car traveling @ 90km/h strikes a tree. The front end of the car compresses and the driver comes to...

*Monday, December 14, 2015 by Jess*

**Physics**

A roller coaster cart of mass m = 293 kg starts stationary at point A, where h1 = 23.3 m and a while later is at B, where h2 = 8.4 m. The acceleration of gravity is 9.8 m/s^2. What is the speed of the cart at B, ignoring the effect of friction?

*Monday, December 14, 2015 by George*

**physics**

A uniform meter stick of mass 30 g is used to suspend three objects as follows: 20 g at 0.01 m, 30 g at 0.42 m and 35 g at 0.9 m. Where could you place your finger to balance the stick in the horizontal position?

*Monday, December 14, 2015 by CO*

**physics **

An Olympic high jumper starts running. As she approaches the bar, she pushes off the ground and lifts her body off the ground and flies over the bar. She then falls down into a large padding on the ground. Describe the energy transformation: The _________ energy in food that ...

*Monday, December 14, 2015 by Edith De Bonilla*

**Physics **

The curve y = 11x - 24 - x^2 cuts the x-axis at points A and B, and PN is the greatest positive value of the y coordinate. Show that 2 PN • AB equals three times the area bounded by that portion of the curve which lies in the first quadrant. Kinda confused on how to do this

*Monday, December 14, 2015 by Pip Paladins*

**Calculus, Physics**

The curve y = 11x - 24 - x^2 cuts the x-axis at points A and B, and PN is the greatest positive value of the y coordinate. Show that 2 PN • AB equals three times the area bounded by that portion of the curve which lies in the first quadrant. Kinda confused on how to do this

*Monday, December 14, 2015 by Pip Paladins*

**physics**

determine the energy stored in a 2m long wire of cross sectional area 0.5mm^2 kf the force of 50N is applied to it.

*Monday, December 14, 2015 by jay*

**Physics**

In the bloodstream, an erythrocyte (red blood cell) of mass m moves with velocity v to the right. Ir collides head-on with a leukocyte (white blood cell) of twice its mass moving to the left with three times its speed. After the collision, the became stuck together. What would...

*Monday, December 14, 2015 by Eric*

**Physics**

A spring with k=1400N/m is firmly anchored to the bottom of a swimming pool. A diver in full SCUBA gear with total mass of 100kg and density of 0.65g/cm3 holds on to the top of the spring. The system reaches a new static equilibrium. After the print is elongated by a length ...

*Monday, December 14, 2015 by Eric*

**Physics**

A certain mass of water at the top of Niagara Falls has a temperature of +10.0 degrees Celsius. It falls a distance of 50m. Assuming that all its potential energy is converted into thermal energy, calculate the temperature of the mass of water at the bottom of the falls.

*Monday, December 14, 2015 by Josée*

**Physics**

An astronaut on board a spacecraft is in orbit around the earth in uniform circular motion. Is her velocity speed and acceleration constant?

*Monday, December 14, 2015 by Haylee*

**Physics**

the top sprinter in the world can reach a terminal speed of 50km/h, in 20m. Assuming the acceleration to be constant, compute the acceleration such an individual experiences, and compare it (in percentage form) to the acceleration of gravity.

*Monday, December 14, 2015 by Haylee*

**Physics**

In the hydrogen atom, the distance between the electron and the proton is 5x10^-11m. a)Compute the magnitude of the gravitational force FG between the electron and the proton b)Compute the magnitude of the electrical force FE between the electron and the proton c)How many ...

*Monday, December 14, 2015 by Val*

**Physics**

A standard man uses crutches. The crutches each make an angle of 25 degrees with the vertical. Half the standard man's weight is supported by the crutches; Assuming the standard man is motionless, find the magnitude of the force supported by each crutch.

*Monday, December 14, 2015 by Irma*

**PHYSICS**

If there is no dark matter, in order to explain our observations, our concepts of an important building block of the universe have to be incorrect. What is that building block and why do Astronomers overwhelmingly favor dark matter, which they cannot see, to explain our ...

*Monday, December 14, 2015 by AJ*

**Physics Help**

A projectile is fired at an upward angle of 60 degrees with a speed of 100m/s. It lands on a plateau 150m higher. What is the projectile's speed the moment before it strikes the plateau? I'm thinking to just use the kinematic equation Vf^2= Vi^2 + 2aΔy. Am I correct?

*Sunday, December 13, 2015 by George*

**Physics **

A tennis ball initially moves with a velocity of 27.0 m/s horizontally to the right. A tennis racket strikes the ball, giving it a velocity of 27.0 m/s to the left. Treat the collision as elastic and the ball and racket as particles of mass 0.0580 kg and 0.272 kg respectively...

*Sunday, December 13, 2015 by Physics idiot*

**Physics **

A missile of mass 1.20 102 kg is fired from a plane of mass 5.10 103 kg initially moving at a speed of 3.35 102 m/s. If the speed of the missile relative to the plane is 1.21 103 m/s, what is the final velocity of the plane? HELP I have no idea how to do this

*Sunday, December 13, 2015 by Physics nerd*

**Physics **

A 810.0 kg pink grapefruit is accelerated horizontally from rest to velocity of 11.0 m/s in 5.00 seconds by horizontal force. How much work is done on the pink grapefruit assume no function?

*Sunday, December 13, 2015 by .*

**Physics**

A 2-kg small block is dropped from rest. The spring has a constant k = 500N/m. If the entire track is frictionless except for the 1m between points B and C, where the coefficient of kinetic friction is 0.15, find he maximum compression of the spring.

*Sunday, December 13, 2015 by Adam*

**Physics**

A fire hose ejects a stream of water at an angle of 35.8 ° above the horizontal. The water leaves the nozzle with a speed of 21.9 m/s. Assuming that the water behaves like a projectile, how far from a building should the fire hose be located to hit the highest possible fire?

*Sunday, December 13, 2015 by Nicole*