# physics please HELP !

74,851 results, page 87-
## Physics

A sample of charcoal from an archaeological site contains 55 g of carbon and decays at a rate of .877 Bq. How old is it? ok I am totally lost, I don't know where to start -
## physics

TWO LOCOMOTIVES APPROACH EACH OTHER ON PARALLEL TRACKS. EACH HAS A SPEED OF 95KM/H WITH RESPECT TO THE GROUNG. IF THEY ARE INITIALLY 8.5KM APART, HOW LONG WILL IT BE BEFORE THEY REACH EACH OTHER? -
## physics urgent please

Give an example of projectile motion;include in your explantion the term "velocity" , "accleration" and "displacement", orginality in your example will be appreciated? -
## physics

what is the magnitude of the centripetal force acting on the earth as it orbits the sun assuming a circular orbital speed of 3.00 X 10^4 meters per second -
## physics

If a pull of 350 N accelerates a 38-kg child on ice skates at a rate of 7.3 \frac{m}{s^2}, what is the frictional force acting on the skate? -
## science(physics)

give an example of projectile motion;include in your explantion the term velocity , accleration and displacement orginality in your example will be appreciated? -
## Physics

Calculate the height through which a crane can lift a load of 4 ton when it's motor of 4 H.P operates for 10 sec. Acceleration due to gravity is 10 m/s2 -
## Physics

a 35 kg child slides down a 26 degree incline. the coefficient of kinetic friction is 0.33. what is her speed after sliding for 2.5 seconds starting from rest? -
## Physics

An outfielder throws a baseball to home plate with a velocity of +15 m/s and an angle of 30°. When will the ball reach its highest altitude? (Points : 3) 1.2 s 1.5 s 0.77 s 0.50 s -
## Physics

A crate with mass 26.0kg initially at rest on a warehouse floor is acted on by a net horizontal force of 160N . -
## Physics

Calculate the vertical distance an object dropped from rest would cover in 12s if it fell freely without air resistance. -
## Physics

Two people pushing a stalled car from rest generate a net force of +840N for 5.0s. What is the cars final velocity? -
## physics

CALCULATE THE ACCELERATION FOR A 10.0 KG BLOCK WHICH IS BEING PULLED UP A 35.0 DEGREE SLOPE BY A FORCE OF 140 N IF THE COEFFICIENT OF SLIDING FRICTION IS 0.100 -
## physics

A stone of mass 2.8kg is projected upward with a speed of 5m/s. calculate the maximum height reached. use g=10m/s square. -
## Physics

A 172 N sign is supported in a motionless position by two ropes that each make an angle of 36° with the horizontal. What force does each rope exert? -
## Physics

A plane has an airspeed of 200 m/s due north and is subject to a westerly wind of 50 m/s. What is the planes speed relative to the ground? -
## physics

How much force does an 71 {\rm kg} astronaut exert on his chair while sitting at rest on the launch pad? Express your answer using two significant figures. -
## physics

A 25000 kg rock is located at a distance of 7.6 x 108 m away from a small planet of mass 7.8 x 1023 kg. What is the mutual force of attraction between these two -
## Physics

Suppose the surface (radius = r) of the space station in the figure is rotating at 38.6 m/s. What must be the value of r for the astronauts to weigh one-half of their earth-weight? -
## physics

calculate the net charge on a substance consisting of a combination of 2.6e13 protons and 6.0e13 electrons. answer in units of C. -
## physics

Two sinusoidal waves of the same frequency travel in the same direction along a string. If ym1 = 4.2 cm, ym2 = 5.9 cm, ö1 = 0, and ö2 = /5 rad, what is the amplitude (in cm) of the resultant wave? -
## physics

a toaster draws a current of 13.0A and has an electric potential difference of 120.V. For how long must it remain on to use 2.0x10^5J of electrical energy? -
## Physics

A car whose brakes are locked skids to a stop in 200 ft from an initial velocity of 50 mi/hr. Find the coefficient of sliding friction. -
## physics

a motorisrt accelerates their car to 36m/s before realising they are over the speed limit and decelerates to 32m/s. calculate the distance traveled -
## physics

a person whos mass is 102 kg stands on a beam supported by two ropes , A and B, he is standing on one foot to help you solve this problem. -
## Physics- Lenses

A planoconvex lens is to have a focal length of 28.5 cm. If made from fused quartz, what must be the radius of curvature of the convex surface? -
## physics

How much work in eV is required to bring three charges of 6.8x10-18C from a great distance apart to 5.04x10-9m from one another (at the corners of an equilateral triangle)? -
## Physics

A light-rail commuter train blows its 200 Hz horn as it approaches a crossing. The speed of sound is 332 m/s. -
## physics

A glacier advances at 4.3 × 10−6 cm/s.How far will it move in 6.4 years? Assume there is 365 days each year. Answer in units of cm. Thanks in advance!! -
## physics

if a cyclist takes one minute to comple half revolution on a circular path 120 m radius.what is the average velocity? -
## Physics

What is the magnitude of the electric field at a point midway between a −8.3μC and a +5.4μC charge 10cm apart? Assume no other charges are nearby. -
## PHYSICS

A grinding wheel 0.3m in diametre has amass of 5kg is rotating at an angular velocity of 2300rev/min.what is the kinetic energy? -
## PHYSICS

A grinding wheel 0.3m in diametre has amass of 5kg is rotating at an angular velocity of 2300rev/min.what is the kinetic energy? -
## physics

Determine the moment of inertia for three children weighing 57.0 lb, 42.0 lb and 78 lb sitting at different points on the edge of a rotating merry-go-round, which has a radius of 12 ft. -
## physics

In one mole or 18 grams of water, the total negative charge of all the electrons is: a. zero because its electrically neutral. b. less than one C c. almost 100,000 C. d. almost one million C. e. none of these -
## physics

A robot arm expends 15J of work to extend a spring 10cm from its equilibrium position. How much force is required? -
## Physics

Suppose the surface (radius = r) of the space station in the figure is rotating at 38.6 m/s. What must be the value of r for the astronauts to weigh one-half of their earth-weight? -
## physics

Calculate the gauge pressure inside a soap bubble 0.0002m in radius using the surface tension for soapy water -
## Physics!!!

How much work W must be done on a particle with a mass of m to accelerate it from rest to a speed of 0.899c ? Express your answer as a multiple of mc^2 to three significant figures. -
## Physics

the potential energy of a particle varies with velocity v as U equals to Av3/v + B where A and B are constant dimensional formula A/B is (1) ML-1T (2) M-1LT (3) L-1T-1 (4) MLT-1 -
## physics

a string of cross section 2 cm^2 is doubled in length by the application of a longitudinal force 2*10^5dynes.the young"s modulus is: 1.10^5 dyne/cm^2 -
## physics

The speed of sound in air is about 330m/sec. If a lighting flash occurs 5.5 seconds before you hear the thunder how far away from you was the strike? -
## physics

Two wires run parallel to each other with currents I1 = -60.3 A, and I2 = 44.1 A. If they are a = 0.12 m apart, what is the magnitude of the force (N) per meter of length? I used the formula (f/L)=Uo(I1)(I2)/(2(pi)(r)) I got 4.43810^-2(N/m)but it was -
## Physics

A player kicks a football from ground level with a velocity of magnitude 31.0 m/s at an angle of 30.0 degrees above the horizontal. What is its maximum height? -
## Maths/Physics

Is it possible to share a four fingered Kit Kat equally between 5 people if you can only break any one piece in half? Prove whether it is possible or impossible. -
## physics

Use these magnitudes of the forces of gravity at Earth's surface to determine the masses of the objects on which they act A)0.98N. B)62N C)44.5MN -
## physics

Time() 0 2 4 6 8 10 12 14 16 Velocity() 0 0 2 5 10 15 20 22 22 By measuring the slope of your curve, find the magnitude of the instantaneous acceleration at times = 9s i don't know how to solve it -
## Physics

A baseball with a mass of 0.145 kg is thrown straight down at the ground. At a particular speed, it has a drag force of 0.4 N acting on it. What is its acceleration at that time? a. -7.0 m/s2 b. -2.8 m/s2 c. -9.8 m/s2 d. -12.6 m/s2 -
## physics

A satellite orbits at an average altitude of h = 423 km. How long does it need to complete one full orbit? Use REarth = 6370 km and mEarth = 5.98 x 10^24 kg -
## physics

Imagine having an 80-turn coil with radius of 5.0 cm and resistance of 30 Ù. At what rate must a perpendicular magnetic field change to produce a current of 4.0 A? -
## physics

find the equilibrium of two is N forces acting upon a body,when the angle betweenthem is a)90degrees b)120degrees c)180degrees d)10degrees e)45degrees -
## General Physics 2

three charges, +2.5×10^-6, -4.8×10^-6, and -6.3×10^-6, are located at (-20m,0.15m), (0.50m,-0.35m), and (-0.42m,-0.32m) respectively. What is the electric field at the origin? -
## 11th grade physics

the horizontal range of a projectile is 4 root 3 times of its maximum height. calculate the angle of projection. -
## 11th grade physics

if action and reaction are always equal and opposite, why don't they always cancel each other and leave no force for acceleration of the body? -
## physics

Use these magnitudes of the forces of gravity at Earth's surface to determine the masses of the objects on which they act A)0.98N. B)62N C)44.5MN -
## Physics

I am driving to Atlanta on the I-85 in my G35 Coupe at 40.0 m/s and I pass a cop. Will I get a ticket? The speed limit is 70.0 mi/h, 1 mile= 1.609 km = 1609 m. -
## physics

How much work in eV is required to bring three charges of 5.4x10-19C from a great distance apart to 3.76x10-8m from one another (at the corners of an equilateral triangle)? -
## physics

Two comets, each of mass 6500 kg and traveling 88 m/s in opposite directions, collide head-on and come to rest. How much energy is produced in this collision? -
## PHYSICS

How much work did the movers do (horizontally) pushing a 140-kg crate 10.1 m across a rough floor without acceleration, if the effective coefficient of friction was 0.60? -
## physics

When 1.60 multiplied by 105 J of heat enters a cherry pie initially at 20.0°C, its entropy increases by 470 J/K. What is its final temperature (C)? -
## Physics

How much work did the movers do (horizontally) pushing a 140-kg crate 10.1 m across a rough floor without acceleration, if the effective coefficient of friction was 0.60? -
## Physics

Carbon dioxide forms into a solid (dry ice) at approximately -157°F. What temperature in degrees Celsius does this correspond to? -
## Intergated chemistry/physics

What is the momentum of a 100 kilogram football player moving with a speed of 3.5 meters/second. The units should be written as kg m/s. -
## physics

brakes are applied in bringing in a 1200-kg car moving at 25 m/s to rest in 20.0 s. show that the amount of braking force is 1500n. -
## physics

Hm0 dug b00b pass taik pay 0ff.blue medcare x x1234567.sead h0sp -
## Physics

When a compact disk with a 12.0-cm diameter is rotating at 4.2 rad/s, what is (a) the linear speed and (b) the centripetal acceleration of a point on its outer rim? -
## physics

Two forces are applied to a car in an effort to move it, as shown in the following figure, where F1 = 416 N and F2 = 363 N. (Assume up and to the right as positive directions.) -
## Physics

two small spheres lie 1.5 meters apart and carry identical charges. How large is the charge on each if a sphere experiences a force of 2.0 N. -
## Physics

A 92 kg disk, with a radius of 0.97 meters, is rotating at 562 rpm. What is its angular momentum, to the nearest tenth of a Joule*sec? -
## Physics

A girl is floating in a freshwater lake with her head just above the water. If she weighs 395 N, what is the volume of the submerged part of her body? -
## physics

from point A, a boy walks 4 m to the east,2 m to the sout, 4 m to the west , and finally, 2 m to the north , find the distance he travelled and his displacement -
## physics

a framed painting weighs 220 newtons. the 2 wires support an angle of 120 degrees with each other. what are the tensions on the wire? -
## Physics

charges of -6nC and 4nC are 3m apart.(a)Determine the force they exert on each other.(b) the net electric field intensity at a point midway between them. -
## Physics

You drop a rock from a 300-meter cliff. How long will it take to reach the ground? Assume it has no significant air resistance -
## physics

A particular jet aircraft must reach a speed of 43 m/s in order to take-off. If the acceleration of the plane is 1329 m/s2, the minimum length of the runway is Answermeters -
## Physics Need help plz

An 1900 kg car is traveling with a speed of (22 +- .22) m/s. With what maximum accuracy can its position be determined? delta x= in meters Can someone please help me out I am lost on this on...Thank you -
## physics

Two identical balls A and B are released from the positions .They collide elastically on horizontal position MN. The ratio of the heights attained by A and B after collision will be ? -
## Physics

An austronaut orbits the Earth in the space shuttle, in one complete orbit, is the magnitude of thr displacement the same as the distance traveled? -
## explian why please its physics

expliain y the very high specific heat capacity of water leads to formation of land and sea breezes??? -
## physics

When 1.60 multiplied by 105 J of heat enters a cherry pie initially at 20.0°C, its entropy increases by 470 J/K. What is its final temperature? -
## physics

How fast a Ford Focus car weighing 1200 kg should be moving to have the same momentum as the bullet? Express your answer in miles/hr. -
## physics

What average force is needed to accelerate a 6.00-gram pellet from rest to 110 over a distance of 0.800 along the barrel of a rifle? -
## Physics

A rocket blasts off with acceleration of 5 m/s squared. After 1 min it runs out of fuel. What is the max height and total time in the air? -
## physics(optics)

The critical angle between an equilateral prism and air is 45 degrees.if the incident ray is perpendicular to the refracting surface,then what happens? -
## physics

Four 6.0 kg spheres are located at the corners of a square of side 0.70 m. Calculate the magnitude and direction of the gravitational force on one sphere due to the other three. -
## Physics

A car slows down uniformly from a speed of 29.0 m/s to rest in 8.00s. How far does it travel in that time. - - I know that the equation is X = X0 + V0(t) + .5(at^2) I cant remeber where to put what numbers though. Thanks for the help! -
## physics

water 20 degrees celsius flows through a 25 mm diameter pipe at a rate of 50 liters per minute. is this laminar or turbulant flow or both? -
## Physics

a particle moving with a acceleration travels 24m and 64m in the first two consecutive intervals of 4 seconds each.find its initial velocity -
## physics

When 1.60 multiplied by 105 J of heat enters a cherry pie initially at 20.0°C, its entropy increases by 470 J/K. What is its final temperature (C)? -
## physics

A pump slowly lifts 3.0*10^6 kg of water an average distance of 80.0m in 12minutes. 1) how much work is done in the first 12 minutes? 2)How much power is delivered by the pumps? -
## Physics

3 particles of masses m1 = 1.5 kg , m2 = 2.5 kg and m3 = 3.5 kg form an equilateral triangle of edge length l= 135 cm. Determine the center of mass of the system. -
## Physics

A stone thrown upward to just reach the top of a palm tree that is 8.2m tall. Calculate the initial speed that is require -
## physics

A young boy swings a yo-yo horizontally above his head so that the yo-yo has a centripetal acceleration of 275 m/s2. If the yo-yo's string is 0.55 m long, what is the yo-yo's tangential speed? -
## physics

A 600 kg car is moving on a level road at 30 m/s. How large of a braking force is needed to stop it in a distance of 75m? -
## Physics

Suppose the surface (radius = r) of the space station in the figure is rotating at 38.6 m/s. What must be the value of r for the astronauts to weigh one-half of their earth-weight? -
## Physics

Starting from rest, a skier slides 100 m down a 28 degree slope.How much longer does the run take if the coefficient of kinetic friction is 0.17 instead of 0? -
## PHYSICS

An object is projected horizontally on a floor at 100ft/s. It then decceledates at 10ft/s2. After 5sec what are a.the speed of the body b. The distance it traversed -
## physics

mass = 46 kg, angle 20 degrees, tension 240 newton , coefficient of kinetic friction = 0.5 find acceleration of the object -
## physics

In a gas two waves of length 1m and 1.10m have a frequency difference of 10/3 Hz, the velocity of sound is ? a) 166m/s b) 332m/s c) 83m/s d) 336.7m/s -
## Physics

What is the net force acting on the ring in the diagram?