# Homework Help: Science: Physics

## Recent Homework Questions About Physics

**Physics**

Using heat exchange and conservation of thermal energy, determine the specific heat capacity for your metal. So the data we have is: Aluminium: Mass - 0.004 Initial temp - 100C Final temp: 32C Water: Mass -0.1 Initial temp - 20C Final temp - 32C I know that the formula is mct...

**physics**

What is the energy of a photon of yellow light with a frequency of 5.14 Ã— 1014 Hz?

**physics question**

A skateboarder at a skate park rides along the path shown in (Figure 1) .a=2.7 m and b=1.0m Part A If the speed of the skateboarder at point A is v=1.6m/s, what is her speed at point B? Assume that friction is negligible.

**physics**

A new record for running the stairs of the Empire State Building was set on February 3, 2003. The 86 flights, with a total of 1576 steps, was run in 9 minutes and 33 seconds. If the height gain of each step was 0.20 m, and the mass of the runner was 70 kg , what was his ...

**Physics 30**

an 1100 kg car accelerates from rest at 3.4 m/s2. if the horizontal force exetred on the wheels by the road is 5600 N, what force must be resisting the motion of the car? use a free body diagram to illustrate your answer

**PHYSICS HELP**

A 0.26-kg rock is thrown vertically upward from the top of a cliff that is 31 m high. When it hits the ground at the base of the cliff, the rock has a speed of 29 m/s . a.Assuming that air resistance can be ignored, find the initial speed of the rock . v0= M/S b. Find the ...

**Physics**

an 1100 kg car accelerates from rest at 3.4 m/s2. if the horizontal force exerted on the wheels by the road is 5600 N, what force must be resisting the motion of the car? use a free body diagram to illustrate your answer.

**physics**

Pushing on the pump of a soap dispenser compresses a small spring. When the spring is compressed 0.55 cm , its potential energy is 0.0020 J a.What is the force constant of the spring? i found the fist answer is 130N/M B. What compression is required for the spring potential ...

**physics**

A skier starts at rest and glides (without friction) directly down the fall line from the highest point of a giant snowball with a radius of r=31.7 m . The skier can be observed as a point mass and the air resistance is negligible. What speed v does the skier have when she ...

**Physics**

An electric kettle rated accurately at 2.5kw is used to heat 3kg of water from 15% to boiling point it takes 9.5 minute. Then the amount of heat that has been lost is

**Physics**

Derive an expression for escape speed of satellite.

**Physics**

Calculate the force acting on a body of mass 10 kg moving with a uniform velocity of 2m/s.

**Physics**

A spring balance has a scale that reads from 0 to 5 kg. The length of scale is 20 cm.a body suspended from this spring, when displaced and released ,oscillates with period of 0.60s.what is the weight of body.

**Physics**

Two forces whose magnitude are in the ratio 3:5 give a resultant of 28N.if the angle of inclination is 60, find the magnitude of each force.

**Physics**

A boat travels at 15 m/s in a direction 45° east of north. The boat then turns and travels at 18 m/s in a direction 5° north of east. What is the magnitude of the boat’s resultant velocity? Round your answer to the nearest whole number. What is the direction of the boat’...

**Physics**

A boat travels at 15 m/s in a direction 45° east of north. The boat then turns and travels at 18 m/s in a direction 5° north of east. What is the magnitude of the boat’s resultant velocity? Round your answer to the nearest whole number. What is the direction of the boat’...

**physics**

from newton's second law of motion derive the formulae F=ma

**physics**

Two dimensions. In the figure, three point particles are fixed in place in an xy plane. Particle A has mass mA = 4 g, particle B has mass 2.00mA, and particle C has mass 3.00mA. A fourth particle D, with mass 4.00mA, is to be placed near the other three particles. What (a) x ...

**physics**

A swimmer sets off from one bank. The velocity of the swimmer relative to the water is 1.2 m / s at 45° to the river banks, as shown in Fig. 1.1. In the space below, draw a scale diagram to determine the resultant velocity of the swimmer relative to the river banks. This ...

**Physics**

A river is flowing at 3mps.A man can swim in still water at a speed of 6mps.The angle at which the bank at which the swimmer should start ,so that he may cross the river along the shortest distance is?

**Physics**

Calculate the distance between the two proton such that the electrical repulsive force between them is equal to the weight of either

**physics question**

a forklift lifts a 100 kg of concrete through a vertical height of 16 m in 20 sec.the power applied to the motor un driving the forklift is 1kw.a) calculate the work done every second in lifting the concrete block.b) what is the power output of the motor?c) what is the ...

**physics**

a car of mass 1000 kg moving at a speed of 20 m/s is brought to rest through a distance of 100 m by applying the brakes.a)calculate the accleration of the car.b) calculate the force by the brakes assuming that is constant and there is no other resistance.c)calculate the work ...

**physics 1**

A floating cube is 10 cm on a side and has a density of 800 kg/m^3 . IT is floating in fresh water that has a density of 1000 kg/m^3. what percent of the cube is above the surface of the water? Again, my professor says it is 20%, but how??

**physics 1**

Glass has a density of about 2500 Kg/m^3. fresh water has a density of 1000 kg/m^3. if a 5 kg block of glass is sitting on the bottom of a freshwater fish tank, what is the normal force on the floor of the tank? 30N is what my professor says is correct, but im confused how?

**physics**

A bicycle traveling at 9.8 m/s needs to stop in a time of 5s. what coefficient of friction is required? Answer:0.2, can someone possibly show me how this is the answer? i keep getting something else.

**physics**

A 2.0 kg mass is sliding on a flat surface, with an initial speed of 20 m/s, and a coefficient of friction of 0.2. what is the magnitude of its acceleration? I know the answer is 2.0 m/s^2, but can someone show me how ?

**physics**

two forces are acting on an object. F1= 60 N is horizontal while F2= -80N is vertical, what is the magnitude of the net force acting on the object? The answer is 100 N, can some one please explain it though?

**Physics**

An iron piece of mass 360g and a density of 6g/cm if suspended by a rope so that is partially submerged in oil of density 0.9g/cm find the tension (force) in the string

**Physics**

An iron piece of mass 360g and a density of 6g/cm if suspended by a rope so that is partially submerged in oil of density 0.9g/cm find the tension (force) in the string

**AP Physics**

A person with the weight of 691 N stands on a bathroom scale in a motionless elevator. The elevator begins to move and the scale momentarily changes to 499 N. (a) Draw a force diagram of the situation. (b) Create a qualitative vertical equation for this situation. (c) ...

**Physics**

A person with the weight of 691 N stands on a bathroom scale in a motionless elevator. The elevator begins to move and the scale momentarily changes to 499 N. (a) Draw a force diagram of the situation. (b) Create a qualitative vertical equation for this situation. (c) ...

**physics**

a d'arsonval meter movement deflects to 0.8mA. what is the peak value of the alternating current if the instrument uses full-wave rectification?

**Physics**

A pilot checks her instruments and finds that her airspeed is 345 km/h and that she is heading in a direction [S40ºW]. A radio report tells her that the wind velocity is 85 km/h [NW]. What is the velocity of her plane relative to the ground? I tried to draw this out, but ...

**physics**

the current through a meter movement is 150 micro amperes. what is the dc value if the instrument uses half-wave rectification?

**physics**

A car has a velocity of 25m and accelerates uniformly to 45m/s in 10seconds.what is the acceleration?

**physics**

When a 6kg mass is lifted from the ground to a height of 12 meters, the gravitational potential energy of the mass increases. Calculate how much will be the increase?

**physics**

When a 6kg mass is lifted from ground to a height of 12 meters,the gravitational potential energy of the mass increases. Calculate how much will be the increase?

**physics**

1,500J of heat energy is added to ice water and it causes the water temperature to rise by 4°C (not 40°C).what is the Mass of the ice water?

**AP physics (simple experiment question)**

the 440Hz and the 441 Hz tone bars are to be placed horizontally on stable surface. strike both tone bars with the hammer. 10. what do you hear? report any pattern you hear to the sound generated. 11. when striking a single tone bar sprinkles some powder or sand into the bar ...

**Physics**

A modern computer central processing unit chip (CPU) runs with a clock speed of 2.7 GHz. It can execute one operation in each of these clock cycles. (a) how many seconds long is one clock cycle? (b) Electrical signals travel at the speed of light How far can an electrical ...

**Physics**

An object of mass 2kg on a plane inclined at angle 40degree and whose coefficient of dynamic friction is 0.3 is connected to another mass of 1kg which hangs vertically over a frictionless pulley. Obtain the acceleration of the system

**physics**

A cable is 100 m long and has a cross-section area of 1 mm2. A 1000-N force is applied to stretch the cable. If Young’s modulus for the cable is 1.0x1011 N/m2 , how far does it stretch? A. 10. m B. 1.0 m C. 0.10 m D. 0.01 m E. 0.001 m

**physics**

A heat engine performs 272 J of work in each cycle while also delivering 241 J of heat to the cold reservoir. Find the efficiency of the heat engine. Give your answer in percent (%) and with 3 significant figures.

**physics and motion**

The Grizwald’s have just chopped down a Christmas tree and have decided to pull it out of the woods on a sled over the snow. Clark has attached a rope to the sled and is pulling the tree/sled system (mass = 22 kg) with a force of 50.0 N at an angle of 32˚ above the ...

**physics**

I am looking out a window that is 1.3m tall. A water balloon suddenly drops across the entire length of the window in .22 seconds. How far above the window was it dropped?

**physics**

A 37.0 g ice cube at -15.0 degreesC is placed in 224 g of water at 48.0 degreesC. Find the final temperature of the system when equilibrium is reached. Ignore the heat capacity of the container and assume this is in a calorimeter, i.e. the system is thermally insulated from ...

**physics**

A bomb dropped from a balloon reaches the ground in 30seconds.Determine the height of the balloon if it is ascending with a speed of 100cm^-1 when the bomb is dropped.

**Physics**

You are launching Robin Hood out of a cannon and over the wall of the castle to rescue the Maid Marion. He would like to clear the castle wall by as much as possible. The cannon is stuck at an angle of 45 degrees from the ground and will launch him with a speed of 25 m/s. How ...

**Physics**

A vertical spring has a length of 0.175m when a 0.25kg mass hangs from it, and a length of 0.775m when a 1.9kg mass hangs from it. What is the force constant of the spring in N/m?

**Physics**

Amazon is bringing me a box of shark repellent to my small island (about a 10 m diameter). They are going to drop it as they fly overhead. The plane flies 125 m above the ground at a speed of 550 m/s. How far away from my island should they drop my supplies so that it lands on...

**Physics**

You are launching Robin Hood out of a cannon and over the wall of the castle to rescue the Maid Marion. He would like to clear the castle wall by as much as possible. The cannon is stuck at an angle of 45 degrees from the ground and will launch him with a speed of 25 m/s. How ...

**Physics**

A person runs off a 10.0-meter high balcony in a horizontal direction at 5.0 m/s. The swimming pool is at ground level 5.5 meters away from the edge of the balcony. Will the person reach the pool? Assume no air resistance. *I'm having trouble with this question. I've tried ...

**Physics**

The angular velocity of an engine increase from 1200 RPM to 3000 RPM in 10 second computer angular acceleration and the number of revolution made during this time.

**Physics**

How much heat is needed to melt 14.3kg of silver that is initially at 44°C?

**Physics**

A cube of ice is taken from the freezer at -9.0°C and placed in a 71-g aluminum calorimeter filled with 261g of water at room temperature of 20.0°C. The final situation is observed to be all water at 13.4°C. What was the mass of the ice cube (in grams)?

**physics**

What airspeed would a plane have to travel to have a groundspeed of 320 km/h [S] if there is a 50.0 km/h wind coming from the northwest?

**Physics**

A dedicated physics student pulls his brand new shiny red wagon along a level road such that the handle makes an angle of 50 degrees with the horizontal road. if he pulls on the handle with a force of 85N, what is the horizontal component of the force he exerts along the ...

**physics**

A closed 2.0-L container holds 3.0 mol of an ideal gas. If 200 J of heat is added, what is the change in internal energy of the system? A. 300 J B. 150 J C. zero D. 100 J E. 200 J -Since there is no mention of work being done I thing the answer is 200J but I want to make sure?

**physics**

Consider a 10 gram sample of a liquid with specific heat 2 J/g*K. By the addition of 400 J, the liquid increases its temperature by 10 K and then boils. Half of the liquid boils away before all the heat is used up. What is the heat of vaporization of the liquid? A. 10 J/g B. ...

**Physics**

Two boys are pulling a girl along on a tobaggan. Each boy pulls on a rope attached to the same point on the front of the tobaggan with a force of 360 N. Using a scale diagram, determine the resultant of the two forces exerted by the boys if their ropes form each of these ...

**physics**

A 37.0 g ice cube at -15.0 degreesC is placed in 224 g of water at 48.0 degreesC. Find the final temperature of the system when equilibrium is reached. Ignore the heat capacity of the container and assume this is in a calorimeter, i.e. the system is thermally insulated from ...

**physics**

What force is needed to accelerate a child on a sled (total mass = 60 kg) at 1.25 m/s2?

**Physics 12**

Two boys are pulling a girl along on a tobaggan. Each boy pulls on a rope attached to the same point on the front of the tobaggan with a force of 360 N. Using a scale diagram, determine the resultant of the two forces exerted by the boys if their ropes form each of these ...

**Physics 11**

A businesswoman is applying a force of 12.0 N [upwards] to carry her briefcase for a horizontal distance of 200.0 m. How much work is she doing on the briefcase?

**physics**

An object with a mass of 34.0 g and a volume of 41.0 + B cm3 is placed in a liquid with a density of 1.25 g/cm3. Find the volume of the part of the object that is NOT submerged in the liquid. Give your answer in cm3 and with 3 significant figures.

**PHYSICS PLS HELP WITH THIS QUESTION !**

A 1100-kg elevator is lifted at a constant speed of 1.5 m/s through a height of 20 m. a)How much work is done by the tension in the elevator cable?How much work is done by gravity? b)How much work is done by gravity?

**physics hw**

A 1100-kg elevator is lifted at a constant speed of 1.5 m/s through a height of 20 m. a)How much work is done by the tension in the elevator cable?How much work is done by gravity? b)How much work is done by gravity?

**Physics**

A hockey puck has a mass of 210 g. If the hockey puck has 73 J of kinetic energy, what is its speed?

**Physics**

A car with a mass of 1500kg is moving at a speed of 50 km/h. What is it's Ek?

**Physics**

a 1.5 kg blue ball moves with a speed of 2.5 m/s collides, another 1.5 kg red ball which is at rest. after collision, the blue ball moves off at an angle of 30 deggress to the original direction of motion and the red ball deflects at an angle of theta to the same axis. find ...

**Physics**

An object of mass M is subject to two constant forces: F1, pointing in the x-direction, and F2, pointing in the y-direction. Show that the motion is one of constant acceleration. Find the magnitude and direction of this uniform acceleration. (Use the following as necessary: M...

**physics**

Initially sliding with a speed of 4.1 m/s, a 1.8 kg block collides with a spring and compresses it 0.37 m before coming to rest. What is the force constant of the spring? k=Nm

**physics help**

At t=1.0s, a 0.49 kg object is falling with a speed of 6.5 m/s. At t=2.0s, it has a kinetic energy of 38 J. What is the kinetic energy of the object at t=1.0s? What is the speed of the object at t=2.0s? How much work was done on the object between t=1.0s and t=2.0s?

**physics**

A 1100-kg elevator is lifted at a constant speed of 1.5 m/s through a height of 20 m. Part A How much work is done by the tension in the elevator cable? Express your answer to two significant figures and include appropriate units. Part B How much work is done by gravity?

**physics**

A boy pulls a bag of baseball bats across a ball field toward the parking lot. The bag of bats has a mass of 6.8 kg, and the boy exerts a horizontal force of 20 N on the bag. As a result, the bag accelerates from rest to a speed of 1.12 m/s in a distance of 5.4 m. Part A What ...

**Physics**

A 100-W light bulb has an average lifetime of 800 h. how many electrons Move through the bulb in its life?

**physics-optics**

Light of wavelength 649nm illuminates two slits, which are 1.6mm apart. A fringe pattern appears on a screen 2.7m from the slits. What is the distance between dark fringe number 4 and dark fringe number 5?

**physics-optics**

Two speakers are separated by a distance of 3.4 m. A point P is placed at 5.7 m from one of the speakers so that they form a right triangle. If the speed of sound in this situation is 340 m/s and the speakers are in phase, what is the lowest frequency for which the intensity ...

**physics-optics**

Two narrow slits are 0.25mm apart. The dark fringe of order 55 is 0.8 degrees from the central bright fringe. What is the wavelength of the light?

**physics-optics**

In a Young's double-slit experiment, the slits are 0.4mm apart and are illuminated by laser light of wavelength 602.4nm. The screen is 3.1m away. What is the number of dark fringes per centimetre?

**Physics**

A cell of emf 2v and internal resistance of 1ohms passes a current through an external load of 9ohms.calculate the potential difference across the cell

**AP Physics 1**

This isnt exactly a hw question... but for anyone who knows: Im considering to take AP Physics next year as a challenge. I'm going to be taking pre-calc next year ( i already took my algebras) and im not too great in math but im good at memorizing and retaining info... will AP...

**Physics-Graivty**

Suppose planet earth suddenly grew in size, so that its radius was twice as large as before. Also suppose that at the same time, its mass also doubled to twice its former mass. If you weight used to be 700 N, what is it on this "new" Earth. Describe why this is the answer ...

**Physics**

A 100-W light bulb has an average lifetime of 800 h. how many electrons Move through the bulb in its life?

**11 grade / physics**

a meter rod is pivoted at the center 5kg body is attched 10cm from the one end 30cm from the pivot at the other side how much mass be connected to keep the meter in equilibrium

**eqilibrium /physics**

a rod 200cm long is pivoted at the 80cm from the one end 3kg body is attched at the one end 80cm away from the pivoted point how far from the other end 5kg body be attched to the rod

**Physics**

At what height above the earth's surface. the acceleration due to gravity will be 1/9th of its value at the earth's surface. Re = 6400km

**physics**

A car of mass 500kg and velocity=36km/h and suddenlybreak applied 150m calculate the force and work done?

**physics**

if f1= 3i + 5j + 6k and f2= 2i + 3j - 4k both measure the newton are displaced by d= 3i - 2j + 4k measure the metre, find the workdone

**physics**

A 6000kg truck travelling north at 5m/s collides with a 4000kg truck moving west at 15m/s,if the two trucks remain locked together after collision,find (a)with what speed and in what direction do they move immediately after collision?(b)what is the lost of kinetic energy of ...

**physics**

A ball is dropped from a height of 8m onto a horizontal floor and rebounds to a height of 12m.what is the coefficient of restitution between the ball and the floor?take g=10m/s^2

**Physics**

An object weighing 1N in air .it got 0.8N weight when it is emerssed in water what is it's loss of weight?

**PHYSICS**

Compare the electric force holding the electron in orbit (r=0.53Ã—10âˆ’10m) around the proton nucleus of the hydrogen atom, with the gravitational force between the same electron and proton. What is the ratio of these two forces?

**PHYSICS**

If that charge is 3.7 μC , by what percentage does the mass of a 31 g comb change during charging?

**Physics**

When an object of height 1cm is kept at a distance 4cm from a concave mirror,its erect image of height 1.5cm is formed at a distance 6cm behind the mirror.find the focallength of mirror,by drawing

**Physics**

A point light source is kept in front of a convex mirror at a distance of 40cm.find the position of image by drawing

**Physics**

An object 5cm high is placed at a distance 60cm in front of a concave mirror of focallength 10cm.find the position and size of the image by drawing.

**Science, Physics**

A particle moves through angular displacement ø on a circular path of radius r. The linear displacement will be

**Physics**

The number of revolution made by a fly wheel change from 300rpm to1500rpm in 10s.Calculate angular acceleration assuming it to be uniform .Also calculate the number of revolution made during the time?