# Homework Help: Science: Physics

## Recent Homework Questions About Physics

Physics
A ball is allowed to fall from the top of the tower 200m high. At the same instant another ball is thrown vertically upwards from the bottom of the tower with velocity of 40m/s. When and where the two balls meet?

Physics 11
Confused about the formula (1/-f)= (1/do)+(1/-di) For locating an image for a convex mirror. A rose is placed 15cm in front of a convex mirror of focal length 10cm. Determine the location of the image using the mirror equation. (1/-10)=(1/15)+(1/-di) -0.1=0.067 + (1/-di) -0....

physics
the linear expansively of the material of a cube is 12*10-6k. if the length of each side of the cube is 10cm,find the area of one face of the cube and the volume of the cube when its temperature is raised by 30k

Physics
Pls what are evanescent waves really

physics
A 72 N force accelerates mass m1 by 5.0 m/s^2. The same force acts on another mass m2. What acceleration will the same force impart to the two masses when they are joined together?

Physics
Two speakers send out sound in phase at a frequency of 779 Hz. When you are the same distance from both speakers you hear a maximum sound. Moving around, you hear essentially no sound when you are 65 cm from one and 85 cm from the other, and again when you are 123 cm from one ...

Physics
Two speakers send out sound in phase at a frequency of 779 Hz. When you are the same distance from both speakers you hear a maximum sound. Moving around, you hear essentially no sound when you are 65 cm from one and 85 cm from the other, and again when you are 123 cm from one ...

Physics
Two instances during which the heating effects of electric current is not required pls

Physics
When a butterfly lands 12 cm from a concave mirror, it's image is 18 cm behind the mirror. Find the focal length 1/f=(1/do)-(1/di) 1/f=(1/12)-(1/18) 1/f=0.0833-0.0555 1/f=0.0277 f=36 I'm pretty confident w/ my math but as I understood, it's do-di if it's behind the mirror, ...

Physics 11
Glycerine has an index of refraction of 1.47. What is the critical angle for a light ray traveling from: a)Glycerin into air b)Glycerin into water a) I know- n1=1.47 n2=1 angle of refraction=90 1.47(sin.anglei)= sin90 1.47(sin.anglei)=1 sin.anglei=0.6803 angle of incidence=42....

Physics 11-Ray Diagrams
I'm doing a ray diagram with an arrow leaning away from a plane mirror. The rays leading from the tip of the arrow to the image on the other side of the mirror lined up perfectly, however for the rays leading from the end of the arrow I can't seem to line it all up so that ...

physics-density
A solid right circular cone of uniform mass density is initially at rest above a body of water, so that its vertex is just touching the water's surface with its axis of symmetry along the vertical. Now, the cone falls into the water, and has zero speed at the instant it ...

Physics
Robin Hood is known for stealing from the rich to give to the poor. He finds himself surrounded by some angry noblemen who demand he return their gold chest. Outnumbered, he takes an arrow from his quiver and fires it straight into the air, scattering the noblemen who are ...

physics
One second after being thrown straight down an object is falling with a speed of 20m/s. How fast will it be falling 2 seconds later

physics
with what minimum acc can a fireman slide down a rope whose breaking strenght is two third of his weight ?

Physics
2 charges of 16 microculomb and 25 microculomb are separated by a distance of 2 metre apart.If another charge of 5 microculomb is placed in the middle of the line joining the 2 charges.Then what is the net force on the 5 coloumb charge

Physics
A water balloon is thrown straight down at 10.0 m/s from a second floor window, 5.00 m above ground level. 1) How fast is the balloon moving when it hits the ground? (Express your answer to three significant figures.)

physics
Given the system shown, consider all surfaces frictionless. If m=0.5kg is released when it is 1.6 m above the base of M=0.3kg, how long after release will m strike the base ?

Physics 11
A student performs an experiment. On her desk, she directs a light ray at the flat surface of an unknown transparent material at an angle to the normal of 47 degrees. The light ray enters the material at an angle to the normal of 34 degrees. What is the index of refraction for...

Physics 11
I'm trying to draw a ray diagram (the image & mirror are already printed I just need to draw the rays) for a plane mirror. I understand the rules for the most part but I am confused about what angle I should be drawing the first ray from the tip of the arrow to the mirror & ...

Physics
A solid right circular cone of uniform mass density is initially at rest above a body of water, so that its vertex is just touching the water's surface with its axis of symmetry along the vertical. Now, the cone falls into the water, and has zero speed at the instant it ...

Physics
Two blocks lie on a triangle as shown in the figure. Block m has a mass of 5 kg and block P has a mass of 14 kg. Assume the inclines and pulleys are frictionless find the tension in the string. They lie with the string resting on the peak of a 110 degree obtuse triangle, each ...

Physics
A crate of mass 106 kg is pulled by a rope on a frictionless surface. The rope makes an angle of 40 0 above the horizontal. If the tension on the string is 1183 N, what is the acceleration of the crate?

Physics
What is the maximum weight of an aircraft with a wing of area 50m sq. flying horizontally, if the velocity of the air over the upper surface of the wing is 150m/s and that of lower surface is 140 m/s.

Physics
Two blocks of identical mass are placed in water. One is made of aluminum, the other of wood. The wood block is noted and therefore floating. Upon which is the buoyant force greater? 1) on the aluminum block, 2) on the wood block or 3) they both experience the same buoyant ...

physics
Two charges q1 = 2e and q2 = - 4e are placed on the x-axis at points (0; 0) and (a; 0) respectively. (a) What is the magnitude and direction of the electrostatic force on q2 due to q1? (b) Suppose a third charge q3 = -e is introduced at the location (b; 0) such that b > a. ...

physics
Instances where the heating effect of current is not required. Plssss helllp

physics
Instances where the heating effect of current is not required. Plssss helllp

Physics
Please someone help..A horizontal pipe 10.0cm in diameter has a smooth reduction to a pipe 5.0cm in diameter. If the pressure of the water in the large pipe is 80000Pa and the pressure in the small pipe is 60000Pa at what rate does water flow through the pipe?

physics
A solid right circular cone of uniform mass density is initially at rest above a body of water so that its vertex is just touching the waters surface with its axis of symmetry along the vertical. Now, the cone falls into the water, and has zero speed at the instant it becomes ...

Physics
The percentage errors in the measurement of mass and speed are 2% and 4%respectively. Then find maximum error in the measurement of K.E?

Physics
Two blocks of identical mass are placed in water. One is made of aluminum, the other of wood. The wood block is noted and therefore floating. Upon which is the buoyant force greater? 1) on the aluminum block, 2) on the wood block or 3) they both experience the same buoyant ...

Physics
The maximum and minimum magnitudes of the resultant of two given vectors are 17N and 7N respectively. If two vectors are at right angles to each other, then find the magnitude of their resultant?

physics
A mass is attached to a horizontal spring and compresses the string by 10 cm (position A). when it is released, it bounces back and stretches the spring by 10 cm (position B). Compare the potential energies at position A and B. The choices are 1). A>B, 2) A=B 3)A<B or 4...

Physics
Find the angle between the vectors A=6i+8j+10k B=6i+8j-10k

Physics
An interplanetary probe speeding in deep space suddenly needs to make a left turn. It is presently traveling at v=20000 m/s , and needs to make a quarter circle turn, continuing at the same tangential speed. It is equipped with an ion thruster rocket capable of ejecting ions ...

Physics
"Two blocks lie on a triangle as shown in the figure.  Block m has a mass of 8 kg and block P has a mass of 21 kg.  Assume the inclines and pulleys are frictionless find the tension in the string." The two blocks are on opposite side of an isosceles triangle with the two ...

Physics
A spring 20 cm long, is stretched to 25 cm by a load of 50N.What will be it's length when stretched by 100N assuming that the elastic limit is not reached F=ke

Physics
A load of mass 80kg is placed in a lift. Calculate the reaction between the floor of the lift and the load when the lift moves upwards: (i) at constant velocity, (ii) with an acceleration 2ms 2 [Take g 9.8ms 2].

physics
T=6.28√1.63 F

physics
A person standing on a vertical cliff a height h above the lake wants to jump into the lake but notices a rock just at the surface level with its furthest edge a distance s from the shore .The person realizes that with a running start it will be possible to just clear the rock...

Physics
Find the unit vector parallel to the vector : C=12i+24j-8k. A.9/7i+5/7j+1/7k B.3/7i+6/7j-2/7k. I think B is correct. Please tell me correct option and method of finding.

Physics
If the vectors A and B are such that |A+B|=|A-B, then find the angle between vectors A and B?

physics
A person standing on a vertical cliff a height h above the lake wants to jump into the lake but notices a rock just at the surface level with its furthest edge a distance s from the shore .The person realizes that with a running start it will be possible to just clear the rock...

physics
A wire of 10 ohm resistance is stretched to transform its original length what will be its new Resistivity and new resistance

physics
Three cities X,Y, and Z are connected by straight highways. City X is 6 km from city Y, city Y is 4 km from city Z, and city X is 5 km from city Z. Find the angle made by the highways XY and YZ?

Physics 11
The diagram shows a collision between a 4.0 kg toy car and a stationary 8.0 kg toy truck. After the collision, the car bounces back at 1.0 m/s while the truck goes forward at 2.0 m/s. Based on these values, are momentum and kinetic energy conserved? Image at bottom of the page...

Physics 11
A 15 kg block is sitting on a level surface. The coefficient of friction between the block and the surface is 0.32. A horizontal force of 25 N is then applied to the block. What is the acceleration of the block while the horizontal force is being applied?

Physics 11
A 15 kg block i

Physics 11
A 4.00 kg block is accelerated along a level surface at 3.00 m/s^2. The applied force is 20.0 N. What is the coefficient of friction between the block and the surface?

Physics
A rectangular track is 40m long 30m broad.A man starts walking from one corner to another . Find the distance travelled and displacement.

Physics
What effect do the following forces have on point? 100N, 30 degrees E of N

physics
the floor of a lorry is 3m high, a plank 5m long is used as an inclined plan to raise some leading the maximum effort required to raise 200N load up the plane

physics
the floor of a lorry is 3m high, a plank 5m longis used as an inclined plan to raise some leading the maximum effort required to raise 200N load up the plane

physics
A ball is dropped downward after 1 sec its velocity is 20m/s another ball is dropped from the same point after 2 sec its velocity will be

Physics
What is the polar notation for a vector that points from the origin to the point (0,5.00) ?

physics
A mountaineer is doing a vertical rappel. She is using a big boulder/stone as her anchor. The Mountain guides association advises that in this type of situation, the boulder should be bigger than a refrigerator. The boulder should be sitting on a surface that is horizontal ...

Physics
What is the displacement from a starting position of (14.0,3.0)m to a final position of (-3.0,-4.0) m?

Physics 1st paper
Two vectors of magnitude 8 unit each are acting at a point making an angle120 degree with each other.determine the magnitude

physics
Two instances during which the heating effect of current is not required

physics
A galvanometer of resistance 50 ohm which gives a full deflection for 1mA is to be adapted to measure currents up to 5A. Calculate the resistance of the resistor required

physics
An object with a height of 12cm is placed 4cm in front of a concave mirror whose radius of curvature is 16cm.

physics
A mountaineer is doing a vertical rappel. She is using a big boulder as her anchor. The Mountain guides association advises that in this type of situation, the boulder should be bigger than a refigerator and should be sitting on a surface that is horizontal rather than sloping...

physics
vector A = a displacement of 20 m due east vector B = a displacement of 30 m north find the magnitude and direction of the vector sum a+b

Physics
5liters of alcohol has a mass of 4kg.the density of alcohol?

physics
Two boxes are connected by a cord running over a pulley. Box A is on a table and Box B is hanging off of the pulley. The system is released from rest and Box B drops a distance D. What is the word done by gravity on box B?

physics
Why is that a lighter object with the higher velocity produces a higher kinetic energy than a heavier object with lower velocity ?

physics
A 5kg block is being moved to 3m by a force of 50N inclined to the horizontal at an angle of 30°. Assuming that a friction force of 5N opposing its motion ,find the acceleration of the block and the work done by the block.

physics
A world-class sprinter can burst out of the blocks to essentially top speed (of about 14.9m/s) in the first 11.6m of the race. How long does it take her to finish the 200m race?

physics
A boat crosses a river of width 174 m in which the current has a uniform speed of 1.13 m/s. The pilot maintains a bearing (i.e., the direc- tion in which the boat points) perpendicular to the river and a throttle setting to give a constant speed of 0.96 m/s relative to the wa...

science - physics
A car us moving with a speed of 60km per h . suddenly the breaks are applied , and the car brought to rest in 10 sec. calculate the accelaration of the car.

Physics
Two particles are moving in a plane; one has the velocity component vix=1m/s, viy=5m/s and the other has the velocity components v2x=4m/s and v2y=3m/s if both started from the same point what is the angle between their paths

Physics
What is the weight (in Newtons) of a 98.17 kg mass?

physics
a boat heads directly across a river with a speed through the water 8m/s. the river current is 2m/s a. what is the magnitude and direction of the boat velocity relative to the earth? b.when the boat reaches the other bank, how far will it be?

Physics
The speed of sound in a classroom is 343m/s. A) A tuning fork of frequency 512Hz is struck. What length of open air tube is required to create a resonant sound at the 1st harmonic? wavelength=v/f=343/512=0.67m L=.5wavelength=.5(.67)= 0.335m B) Fore the same tube, what tuning ...

Physics 11
As water waves from the ocean approach a shallow beach, their wavelengths become shorter. Explain why. v=fwavelength, frequency remains constant & velocity & wavelength decrease or increase w/ water depth. Is that a reasonable answer or are they looking for something else? ...

Physics 11
The speed of water waves is 30cm/s in deep water & 15cm/s in shallow water. If the wavelength in deep water is 1.0cm, what is the wavelength in shallow water? (v2/v1)=(wavelength2/wavelength1) Therefore (15/30)=(wavelength2/1) - 15=30wavlength2 -Wavelength2=0.5cm/s A) Is that ...

Physics !! Help Needed UrGeNtLy!!
A toddler applies a 25.0 N force to a chair over a distance of 2.5 m, the chair is being pushed across a smooth floor against a force of friction (10.0 N resistance). How much work is being done?

Physics
A child leaves her book bag on a slide. The bag, which is at the top of the slide, starts from rest and reaches the bottom in 1.63 s. The mass of the book bag is 2.55 kg, the length of the slide is 2.90 m and the angle of incline is 35.0°. (Assume the +x-axis to be parallel ...

Physics
A toddler applies a 25.0 N force to a chair over a distance of 2.5 m, the chair is being pushed across a smooth floor against a force of friction (10.0 N resistance). How much work is being done?

Physics
A satellite is orbiting a distant planet of mass 9.6e25 kg and radius 86700 km. The satellite orbits at a height of 8610 km above the surface of the planet. a) Determine the acceleration due to gravity at the location of the satellite orbit. b) Determine the velocity of the ...

Physics
A piece of copper ball of mass 20g at 200°c is placed in a copper calomiter of mass 60g containing 50g of water at 30°c ignoring heat losses.calculate the final steady temperature of the mixture

Physics
An object starting from rest travels 20m in first 2 seconds. What will be the distance covered by it in next 4 seconds

Physics
A 0.59g mass of Glynnium goes through a nuclear fission reaction. The energy from the process is used to lift a 97211kg Saturn 5 rocket into orbit. If the mass is transformed with 1% efficiency, what height does the rocket reach? Express your answer in kilometers

physics
An observer on Earth sees an alien vessel approach at a speed of 0.44c. The Enterprise comes to the rescue, overtaking the aliens while moving directly toward Earth at a speed of 0.89c relative to Earth. What is the speed of one vessel as seen by the other?

Physics
A charge of 5.00 ✕ 10^-9 C and a charge of -3.50 ✕ 10^-9 C are separated by a distance of 60.0 cm. Find the position at which a third charge, of 14.0 ✕ 10^-9 C, can be placed so that the net electrostatic force on it is zero.

physics
A detective is investigating a scene of an accident. He measures the length of an automobile's skid marks to find out how fast the automobile was going at the very beginning of the skid. Express In terms of V ( speed), L ( length) and any other suitable variables related to ...

physics
A cargo aircraft has taken off from a mountain. It is climbing at constant speed and at an angle of θ=37 above horizontal. The engines of the plane provide a thrust of F thrust =400kN and the wings provides a lift of F lift=756kN. Drag/air resistance is negligible so F thrust...

physics
The angle of incidence when the angle between the incident ray and refracted ray is 80 degrees is......

physics
lighted matchstick brought near the negatively charged electroscope

physics
A heavy metal beam AB of mass 25Kg is supported at its ends.The beam carries a mass of 150Kg at a distance of 0.75m from end A.If the beam is 2m long, determine the thrust A and B.

physics
A rocket expels gas at the rate of 0.5kg/s.If the force produced by the rocket is 100N,what is the velocity with which the gas is expelled.

physics
a heavy rod AB of length of 5m weighs 50N.The bar is supported in a horizontal position by two vertical strings X and Y.If string X is 0.6m from B and string Y is 1.8 from A,find the tension in the strings.

Physics, fluid mechanics
The temperature of earth atmosphere drops 5°C for every 1km elevation above the earth surface. If the air temperature at ground level is 15°C and 760 mmHg, determine the elevation in m when the pressure is 380 mmHg. Assume the air is an ideal gas with molecular weight of 29 ...

physics
An iron vise falls from rest at a great height. Neglecting air resistance, what is its speed after it has fallen for 5 seconds?

Physics
What is a fatigue fracture

Physics 11
Waves travelling along a string have a wavelength of 2.4m. When the waves reach the fixed end of the string, they are reflected to produce a standing wave pattern. How far from the end are the first 2 antinodes? I know that each wavelength has 2 antinodes so each antinode has ...

physics
a man can row a boat at 5km/hr. in still water and waits to cross a river to a position exactly opposite his starting point. If the river is 5km wide and is flowing at 4km/hr. eastwards find by scale drawing the direction in which he must set off in order to accomplish his ...

physics
A ball is thrown vertically upwards with a velocity of 2 m/s. It is seen at height h twice. Find the sum of the times, measured in seconds from the moment the ball is thrown, at which it is seen at height h. Take g=10m/s² Neglect air resistance.

physics , math
The hydrostatic equation holds not just for air, but for other fluids such as water (air, though it is a gas, is often referred to as a 'fluid') as well. In the case of water the equation becomes even easier, as water (as opposed to air) can be treated as incompressible, ...