Thursday

January 19, 2017
**Physics**

An airplane travelling north at 400 m/s is accelerated due east at a rate of 50m/s^2 for 6 seconds. If the effects of air resistance and gravity are ignored, what is the final speed of the plane? My working: v=vo+at where a=50m/s Vo = 400 m/s t = 6s thus: Vo=400+50(6) =700m/s ...

*Tuesday, January 10, 2017 by Anonymous*

**Physics**

Can someone please tell me how to derive this: its supposed to be projectile motion with spring x = Sqrt (dx*g*1/2*m) +(mgh sin2theta) ---------------------------- (1/2)(k)(sin2theta) all i got is r =v^2sin2theta / g x is displacement of elastic plz help

*Tuesday, January 10, 2017 by Stacy*

**physics**

Water is flowing in a pipe with a circular cross-section area ,and at all point the water completely fills the pipe.At point 1 ,the cross sectiona are of pipe is 0.070 meter square and the fluid velocity is 3.50 meter per second. a.) what is the fluid speed at point in the ...

*Tuesday, January 10, 2017 by cathrena*

**pure physics**

a stone weighs 0.25N in air and o.20N when completely immersed in water. what is the the up thrust on the stone?

*Tuesday, January 10, 2017 by Natasha*

**physics`**

which has more momentum: a snail moving at .001m/s or a 2-ton boulder resting on the ground? why?

*Tuesday, January 10, 2017 by Anonymous*

**Physics**

The man pushes/pulls with a force of 200N. The child and the slide combo has a mass of 30 kg and coefficient of friction is 0.15. The angle between the slide and the ground is 30 degrees. Find the acceleration of the child and what is the frictional forces opposing his efforts

*Tuesday, January 10, 2017 by Thokozanitausi *

**Physics**

Can someone please tell me how to derive this: its supposed to be projectile motion with spring x = Sqrt (dx*g*1/2*m) +(mgh sin2theta) ---------------------------- (1/2)(k)(sin2theta) all i got is r =v^2sin2theta / g x is displacement of elastic plz help

*Monday, January 9, 2017 by Stacy*

**Physics**

An impulse of 25 N*s is exerted on a 0.25 kg baseball traveling 40 m/s west. What is the velocity of the baseball after it has been hit?

*Monday, January 9, 2017 by Garrett*

**Physics**

A ball with mass m=1kg and speed vo=5m/sec elastically collides with a stationary, identical ball (all resting on a frictionless surface so gravity is irrelevant). A student measures the top ball emerging from the collision at at speed vt=4m/sec at an angle Ï´t &...

*Monday, January 9, 2017 by Brian*

**Physics**

A car moving at 60 km/h skids 13 m with locked brakes. How far will the car skid with locked brakes at 180 km/h?

*Monday, January 9, 2017 by JESS*

**Physics**

A great white shark of mass m1, coasting through the water in a nearly frictionless way at speed v1 engulfs a tuna of mass m2=0.10 m1 traveling in the same direction at speed v2 swallowing it in one bite. a) What is the speed of the shark after its meal? b) Did the shark gain...

*Monday, January 9, 2017 by Tom*

**Physics**

the orbital period of the moon is 27.32 days. The international space station has an orbital period of 90 minutes. What is the mean distance between the center of the earth and the center of the international space station? moons orbital radius: 25,201

*Monday, January 9, 2017 by Anonymous*

**Physics**

A bullet of mass m travelling at speed vo in the direction shohwn above strikes a block of mass M and embeds itself in it. The block is sitting on the edge of a frictionless table of height H and is knocked off of the table by the collision. a) What is the speed vb of the ...

*Monday, January 9, 2017 by Joe*

**Physics**

A hammer of mass m falls from rest off of a roof and drops a height H onto your head. a) Assuming that the tool is in actual contact with your head for a time â–³t before it stops and slides off, what is the algebraic expression for the average force it exerts ...

*Monday, January 9, 2017 by Bob*

**Math, Physics**

Calculate Earth's gravitational force on the ISS astronauts while orbiting at an altitude of 401.5 km above Earthâ€™s surface.

*Monday, January 9, 2017 by Hooman*

**physics**

A boy lining a railway bridge 49ft. high, sees a train uproaching with uniform speed and attempt to drop a stone down to railway. He releases the stone when engine is 80ft. away from the point below his position and sees the stone hits in the ground just 3 ft. in front of the ...

*Monday, January 9, 2017 by Athena*

**Physics**

At what frequency would a capacitor of 2.5 microfarads used in a radio circuit have a reactance of 250 ohms

*Monday, January 9, 2017 by Bosola*

**physics**

Only two forces act on an object (mass=3.19Â kg), as in the drawing. Find (a) the magnitude and (b) the direction (relative to the x axis) of the acceleration of the object.

*Sunday, January 8, 2017 by Tyler*

**physics**

An apple crate with a weight of 225 N accelerates along a frictionless surface as the crate is pulled with a force of 14.5 N as shown in the drawing. What is the horizontal acceleration of the crate?

*Sunday, January 8, 2017 by Tyler*

**physics**

A mountain climber, in the process of crossing between two cliffs by a rope, pauses to rest. She weighs 520 N. As the drawing shows, she is closer to the left cliff than to the right cliff, with the result that the tensions in the left and right sides of the rope are not the ...

*Sunday, January 8, 2017 by Tyler*

**physics**

During a storm, a tree limb breaks off and comes to rest across a barbed wire fence at a point that is not in the middle between two fence posts. The limb exerts a downward force ofÂ 253Â N on the wire. The left section of the wire makes an angle ofÂ...

*Sunday, January 8, 2017 by Kyle*

**physics**

One block rests upon a horizontal surface. A second identical block rests upon the first one. The coefficient of static friction between the blocks is the same as the coefficient of static friction between the lower block and the horizontal surface. A horizontal force is ...

*Sunday, January 8, 2017 by Kyle*

**physics**

Traveling at a speed ofÂ 18.0Â 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 isÂ 0.580. What is the speed of the automobile afterÂ&...

*Sunday, January 8, 2017 by Kyle*

**physics**

A person pushes on aÂ 55-kg refrigerator with a horizontal force of -250Â N; the minus sign indicates that the force points in the -x direction. The coefficient of static friction isÂ 0.56. (a) If the refrigerator does not move, what are the ...

*Sunday, January 8, 2017 by Kyle*

**physics**

A car is traveling up a hill that is inclined at an angle Î¸ above the horizontal. Determine the ratio of the magnitude of the normal force to the weight of the car when (a)Â Î¸ =Â 17o and (b)Â Î¸ =Â&...

*Sunday, January 8, 2017 by Kyle*

**physics**

when an apple falls from a tree, and strikes the ground without bouncing, what happens to its momentum?

*Sunday, January 8, 2017 by Anonymous*

**Physics**

A 100 grams mass of a substance has a volume of 150 centmetre cube.Calculate the relative density of the substanc. [density of water pw=1.0gcm^-3]

*Sunday, January 8, 2017 by Angela*

**Physics**

An alloy of iron and silver has a total mass of 30 grams and a volume of 20.4cm^-3.Calculate the mass of iron only and the volume of silver only. [Density of iron=1.62gcm^3 and density of silver=0.9gcm^3]

*Sunday, January 8, 2017 by Juliet*

**Physics**

A piece of metal of volume 250 centimetre cube floats in water when 85 percent of its volume is under water.Calculate the upthrust on the metal. [pw=1.0gcm^-3]

*Sunday, January 8, 2017 by George*

**Physics**

An empty bottle weighs 20 grams and 60 grams when filled completely with water.What would the bottle weigh when filled completely with mercury. [pw=1.0gcm^-3,pm=1.6gcm^-3]

*Sunday, January 8, 2017 by Daniel*

**physics **

when temperature increases from t to # t and the moment of inertia is increase from I to #I. the coefficent of linear expansion is alpha .THE RATIO OF #I\I IS

*Sunday, January 8, 2017 by Anonymous*

**Physics**

A ball thrown with a speed of 100m/s attains a height of 150m (take g=9.8 per second square). Calculate: 1. Time of flight 2. Angle of projection 3. Range

*Sunday, January 8, 2017 by Mk hamman*

**Physics**

What is specific heat

*Sunday, January 8, 2017 by Kritika*

**Science(physics)**

A boy while driving to his school covers at the average speed of 15km/h.On his return trip along the same route, covers at the average speed of 25km/h due to less traffic.What is the average speed for the whole trip

*Sunday, January 8, 2017 by Henry*

**Physics**

The engineer of a passenger train moving at 29.0 m/s sees a freight train 360.m ahead on the track moving at 6.00 m/s. The engineer takes 0.400 seconds to react, and then applies the brakes. At what rate must the passenger train then decelerate in order to avoid a collision? ...

*Saturday, January 7, 2017 by Bob*

**Physics**

A 55kg person pushes on the floor with 800 N of force for 0.25 seconds. How high do they jump off the ground? I know how to find acceleration but I can't find distance.

*Saturday, January 7, 2017 by Bob*

**Physics**

An alloy of iron and silver has a total mass of 30 grams and a volume of 20.4 centimetre cube Calculate the mass of iron only and the volume silver only Please help

*Saturday, January 7, 2017 by Peter*

**Physics**

A piece of metal of volume 250 cetimetre cube floats in water when 85 percent of it's volume is under water.Calculate the upthrust on the metal. 250*85=21250

*Saturday, January 7, 2017 by Jack*

**Physics**

An empty bottle weighs 20g and 60g when filled completely with water.What will it weigh when filled completely with mercury? 20Ã·60=0.3

*Saturday, January 7, 2017 by James*

**Physics**

A student eats a dinner containing 8.0x10 raised to power 6j of energy. He wishes to do an equivalent amount of work in a nearby gym by lifting a 60kg object. How many times must he raise the object to expand this much energy? Assume that he raises it a distance of 2.0m each ...

*Saturday, January 7, 2017 by Reigna*

**physics**

a runner in marathon passes the 5 mile mark at 1 o'clock and the 20 mile mark at 3 o'clock .what is the runners average speed during this time period?

*Saturday, January 7, 2017 by mandy Schwarzenegger*

**physics**

A passengers jet flies from one airport to another 1,200 miles away in 2.5h .Find its average speed.

*Saturday, January 7, 2017 by mandy Schwarzenegger*

**physics**

How far does a car going 25 m/s travel in 5s ? How far would a jet going 250 m/s travel in 5s?

*Saturday, January 7, 2017 by mandy Schwarzenegger*

**Physics**

Find the specific heat of an unknown metal given this data: Mass of the metal = 120 g Temp of the metal = 220 degrees Mass of the water = 30 g Initial Temp of the water = 20 degrees Final Temp of the water = 85.6 degrees Specific Heat of the water = 4.186 J/gram C I get 0.51 J...

*Friday, January 6, 2017 by Anonymous*

**physics**

ifv=(3i+4j+5k)m/s is the instantaneous velocity of a body mass 1.50kg calculate its K.E

*Friday, January 6, 2017 by krushidhar*

**physics**

An ostrich with a mass of 139 kg is running to the right with a velocity of 17 m/s. Find the momentum of the ostrich. Answer in units of kg Â· m/s.

*Thursday, January 5, 2017 by iz*

**physics**

A car is traveling up a hill that is inclined at an angle Î¸ above the horizontal. Determine the ratio of the magnitude of the normal force to the weight of the car when (a)Â Î¸ =Â 17o and (b)Â Î¸ =Â&...

*Thursday, January 5, 2017 by Kyle*

**Physics**

:( physics:(

*Thursday, January 5, 2017 by :(*

**Physics**

A 70.0-kg astronaut pushes to the left on a spacecraft with a force Â in "gravity-free" space. The spacecraft has a total mass of 1.0 Ã— 104 kg. During the push, the astronaut accelerates to the right with an acceleration of 0.36 m/s2. ...

*Thursday, January 5, 2017 by Kyle*

**physics**

When a parachute opens, the air exerts a large drag force on it. This upward force is initially greater than the weight of the sky diver and, thus, slows him down. Suppose the weight of the sky diver isÂ 869Â N and the drag force has a magnitude ofÂ...

*Thursday, January 5, 2017 by Thomas*

**physics**

Two skaters, a man and a woman, are standing on ice. Neglect any friction between the skate blades and the ice. The mass of the man isÂ 84Â kg, and the mass of the woman isÂ 49Â kg. The woman pushes on the man with a force ofÂ&...

*Thursday, January 5, 2017 by Thomas*

**physics**

In a quarter-mile drag race, two cars start simultaneously from rest, and each accelerates at a constant rate until it either reaches its maximum speed or crosses the finish line. Car A has an acceleration of 11.0 m/s2 and a maximum speed of 110 m/s. Car B has an acceleration ...

*Thursday, January 5, 2017 by Thomas*

**physics**

An electron is a subatomic particle (m = 9.11 x 10-31 kg) that is subject to electric forces. An electron moving in the +x direction accelerates from an initial velocity of +7.62Â x 105 m/s to a final velocity ofÂ 2.56Â x 106 m/s while ...

*Thursday, January 5, 2017 by Thomas*

**physics**

Can someone please help me? I am having a really hard time with physics. This is not a test question. It is a practice problem from a review website I am supposed to use, but I am having a really hard time. Can someone at least help me to begin setting up the problem? I would ...

*Thursday, January 5, 2017 by anonymous*

**College Physics**

Two forcesÂ Â andÂ Â are applied to an object whose mass isÂ 5.75Â kg. The larger force isÂ . When both forces point due east, the object's acceleration has a magnitude ofÂ 0.979...

*Thursday, January 5, 2017 by Thomas*

**physics**

a ball is thrown Vatican upward with a velocity of 20.0m/s. a) what is the retardation of the ball? b) what distance does it travel before its comes to rest movementally at the top of its motion? c) what is the time taken for the ball to reach its highest point? d) what is the...

*Thursday, January 5, 2017 by comfort*

**physics (mechanics)**

the potential energy of a system of two particle separated by a distance r is given by u(r) = A/r , where A is constant . find the radial force Fr that each particle exerts on the other

*Thursday, January 5, 2017 by asnke *

**College Physics**

An airplane has a mass ofÂ 3.19Â Ã— 104 kg and takes off under the influence of a constant net force ofÂ 1.56Â Ã— 104 N. What is the net force that acts on the plane'sÂ 82.1-kg pilot?

*Wednesday, January 4, 2017 by Micah*

**Physics**

Draw a block and tackle system of pulleys with a velocity ratio of 5.A block and tackle with a velocity ratio of 5 is used to raise a mass of 25kg through a vertical distanceof 40cm at a steady rate. If the efforts is equal to 60N, determine a)d distance moved by the effort b)...

*Wednesday, January 4, 2017 by Nelson*

**Physics**

3. What happens to the speed of ocean waves as they come close to shore? How can this be explained from what you've learned so far? (this the teacher means what do the lessons have to do with this question) 4. Sound travels faster through wood than through air. Sound also ...

*Wednesday, January 4, 2017 by Manie*

**physics**

A small tiny nail may Pierce an inflated Tyre and remain there without pressure reduction.explain

*Wednesday, January 4, 2017 by Anonymous*

**physics**

A man holds a child on shoulders while watching a football match. How much work has he done if the game last for 2 hours

*Wednesday, January 4, 2017 by paul*

**Physics **

Hello, can someone please check my answers and tell me if they are correct? 1. A laser produces a pulse of light with a speed of 300000000m/s in vacuum in a time 1.70x10^-15s. a) what is the length of the pulse? b) The pulse travels into a piece of glass in which it's ...

*Tuesday, January 3, 2017 by Jon - Please check my answers*

**Physics, math, algebra**

How long will it take a sled to reach the bottom of a hill, if it accelerates at 5.60m/s^2 and has a final velocity at the bottom of the hill of 42.3km/h?

*Tuesday, January 3, 2017 by Anonymous*

**Physics**

Please help with the following question: You are on a planet whose radius is known to be about 4500 km. You then perform the following experiment: You drop a rock from a height of 10.0 m and measure the time of its fall to be 2.65 s. What is the mass of the planet? what ...

*Tuesday, January 3, 2017 by Deila*

**Physics **

when tuning a piano, amusician plays a note that should be at 110Hz while at the same time tapping a 110Hz tuning fork and holding it next to the strings. He hears beats at 4Hz. (A) state and explain what frequencies the piano could be producing (b) explain how the musician ...

*Tuesday, January 3, 2017 by Anonymous*

**Physics**

when tuning a piano, amusician plays a note that should be at 110Hz while at the same time tapping a 110Hz tuning fork and holding it next to the strings. He hears beats at 4Hz. (A) state and explain what frequencies the piano could be producing (b) explain how the musician ...

*Tuesday, January 3, 2017 by Yosef*

**Physics**

3. What happens to the speed of ocean waves as they come close to shore? How can this be explained from what you've learned so far? (this the teacher means what do the lessons have to do with this question) 4. Sound travels faster through wood than through air. Sound also ...

*Tuesday, January 3, 2017 by Manie*

**physics**

a brass rod is 2m long at a certain temperature. What is its length for a temperature rise of 100k, if the expansivity of brass is 18*10

*Tuesday, January 3, 2017 by Maro*

**Physics 1**

a skier of mass 70.0kg is pulled up a slope by a motor-driven cable. How much work is required to pull the skier 60.0 m up a 35.0 degree slope (assumed to be frictionless) at a constant speed of 2.0m/s? The Value of g is 9.81 m/s^2?

*Monday, January 2, 2017 by Brisa*

**Physics**

the coefficient of kinetic friction between both blocks and the table is .200. determine the accelerations of blocks A and B each of which has a mass of 5.0kg The diagram shows a table with two blocks labeled A and B on them. A is connected to a rope that goes over a pulley ...

*Monday, January 2, 2017 by Ally*

**Physics**

5. If a wave has a wavelength of 20m and a speed of 100 m/s, what is the period of the oscillation? v = wavelength / period 100 = 20 / period 100*20 = periodperiod = 20 / 100 2000 s = period OR period = 20 / 100 period = 0.2 s I don't know which one is correct, please help?!

*Monday, January 2, 2017 by Jake*

**physics**

2)A wave is represented by the equation y =2sin.pi(0.5x - 200t) where all distance are measured in centimeters and time in seconds. For this wave, calculate the : (a) frequency (b) wave length (c) speed (d) amplitude step plz

*Monday, January 2, 2017 by tayopo*

**physics help me plz**

A man at the back of a crowd watches a parade by holding a plane mirror just above his head and the parade passes 6m behind his head and the mirror is 0.25m in front of the man. How far does the image appear to be from the man... help i need solution

*Monday, January 2, 2017 by ...*

**Physics**

Water is falling on turbine at a rate of 6000 kg/min the height of fall is 100 m what is the power given to turbine?

*Monday, January 2, 2017 by Saif*

**Physics**

A brass is 2m long at a certain temperature.what is its length for a temperature rise of 100k if the expansivity of brass is 18Ã—10^6k^1

*Monday, January 2, 2017 by Rujo*

**physics**

a woman is draining her fish tank by siphoning the water into an outdoor drain the rectangular tank has footprint area A and depth H . the drain is located a distance D below the surface of the water in the tank , where D>>H . the cross section area of the siphon tube is...

*Sunday, January 1, 2017 by momen*

**Physics**

A bullet of mass 20gm penetrates a board of thickness 10cm and mass 1kg at rest. If the board is free to move,find the thickness to which the bullet will penetrate. I used conservation of momentum to find the combined velocity of bullet and the board in terms of the initial ...

*Saturday, December 31, 2016 by Anirudh*

**Physics**

The focal length of a small concave mirror is 2.5cm in order to use this mirror by dentist .The distance of tooth from mirror is

*Saturday, December 31, 2016 by Trilok*

**Physics **

The occupants of a car traveling at a speed of 30 m/s note that on a particular part of a road their apparent weight is 15% higher than their weight when driving on a flat road. a. Is that part of the road a hill or a dip? b. What is the vertical curvature of the road? Please ...

*Friday, December 30, 2016 by Jorge*

**Physics**

Boxes are moved on a conveyor belt from where they are filled to the packing station 11.3m away. The belt is initially stationary and must finish with zero speed. The most rapid transit is accomplished if the belt accelerates for half the distance, then decelerates for the ...

*Friday, December 30, 2016 by Francis*

**Fun Physics**

A box is given a push up a 16.1Â° incline. When it reaches the bottom again it is only going 0.59 its original speed. Find the coefficient of kinetic friction. *I know the answer is .06 but I don't know how!

*Friday, December 30, 2016 by Rose*

**Physics**

Calculate the pressure due to water experienced by a diver working 25m below the surface of water in dam.(density of water is 1g/cm3 and g=10N/kg.

*Friday, December 30, 2016 by Lewis Williams*

**Physics**

A man can row a boat at a speed of 2metres per second . The man set out to row the boat in a river from A to B. The water in the river flows 0.8metres per second in the opposite direction.Determine the velocity of the boat through the water.

*Friday, December 30, 2016 by Faith*

**physics**

a body is allowed to slide down a frictionless track from rest under gravity . The track end in a circular loop of diameter D . What should be the minimum height of the body in terms of D so that the body successfully complete the loop.

*Friday, December 30, 2016 by Palak*

**physics**

a stone is dropped down a well if it takes 5s to reach the surface of the water calculate how deep the well is , what is the velocity when it reaches the surface of the water

*Friday, December 30, 2016 by Vera djokoto*

**physics**

A body of mass 10 kg is moving with uniform velocity 20m/sec. Calculate its velocity if it enters in a black hole?

*Thursday, December 29, 2016 by rakesh*

**Business mathematics**

In an examination of certain number of candidates 18 passed mathematics, 17 passed physics, 11 passed both mathematics and physics, 1 failed both subjects. Find the number of candidates that passed. i. Mathematics only. ii. Physics only. iii. Total number of candidates that ...

*Thursday, December 29, 2016 by A.A.N*

**physics**

How much work must an ideal refrigerator perform to make 1 kg of ice at -10ï‚°C from 1 kg of water at 20ï‚°C when 20ï‚°C is also its exhaust temperature?

*Wednesday, December 28, 2016 by ap*

**Physics**

what metal is it if, it is 7.14g/mL => Cast Iron.

*Wednesday, December 28, 2016 by Thomas*

**Physics**

I understand this question: 4. If a pendulum completes 40 vibrations in a minute, what is its period? The period is the time for one complete cycle, and if the pendulum takes one minute (or 60 seconds) for 40 vibrational cycles, then it must take 1.5 seconds for one complete ...

*Wednesday, December 28, 2016 by Emily*

**Physics**

If a man travels 7km N 40degree W and 10km East, find the resultant displacement.

*Monday, December 26, 2016 by favour*

**physics**

a Coper wire with wire with a diameter of 1.5mm is joined to an alluminium wire, which has a diameter of 2.3mm. The wire carries a current of 1.2A. What is the current density in each wire?

*Monday, December 26, 2016 by lid*

**Physics **

Two blocks of masses 2.9kg and 3.9 kg are held by string upper and lower and given the acceleration 0.2 in upward direction gind tension

*Monday, December 26, 2016 by AnonymousDilpreet *

**Physics **

Hello, I really don't get something about work and I would like that someone help me, Please. .. Well I have an exercise about two objects that are connected by an ideal rope that pass through a pulley that has a moment of inertia, so my problem is: when I use "energy...

*Saturday, December 24, 2016 by Ross*

**Physics**

Work done by conservative forces change only A)PE of the system B)KE of the system C) ME of the system D)None of these

*Saturday, December 24, 2016 by Nikita*

**Physics**

A simple pendulum is oscillating with an angular amplitude 60Â°.If mass of bob is 50 gram the tension in the string at mean position is(g=10m/s2)

*Saturday, December 24, 2016 by Nikita*

**physics**

A boat of mass 40 kg is at rest.A dog of mass 4 kg moves in the boat with a velocity of 10 m/s.what is the velocity of the boat?

*Saturday, December 24, 2016 by Nikita*

**Physics**

Capacitor c1 and c2 are 4f and 2f respectively are charged as series combination across 100v battery. The two capacitors are disconnected from each other.They are connected +ve plate to +ve plate and -ve plate to -ve plate.calculate the resulting charge on each capacitor

*Saturday, December 24, 2016 by Alice*

**physics**

Geostationary satellites are placed on orbits of radius 4.2Ã—10^4m use this information to deduce g, the acceleration of freely falling body, at this height.

*Friday, December 23, 2016 by Andy *