# physics please HELP !

74,851 results, page 92-
## physics

What is the self-inductance of an air-core solenoid,1m long and 0.05m in diameter,if it has 1400 turns?(a)5.23mH(b)4.84mH(c)3.63mH(d)2.42mH -
## physics

A rocket moves upward, starting from rest with an acceleration of 29.4 m/s2 for 5.65 s. It runs out of fuel at the end of the 5.65 s but does not stop. How high does it rise above the ground? -
## Physics

W.K.T, Magnetic Force qvB=mv^2/r ... n we know how to prove it too.... But how to show that the radius of curvature of the circular path is proportional to the linear momentum of the charge ? -
## physics

how does the shotspotter system can determine the location of a shooting, given the initial muzzle report and the fact that this sound moves out in a spherical wavefront? -
## physics

A train is moving with an initial velocity of 30 m/s the breaks are applied so as to produce uniform acceleration of minus 1.5m/s Calculate the time in which it will come to rest -
## physics homework

0.2kg mass hangs at the end of the wire. what is the tension if the ball is then whirled around in a horizontal circle with tangential velocity of 5m/s -
## physics

A tungsten target is struck by electrons that have been accelerated from rest through a 24.5-kV potential difference. Find the shortest wavelength of the radiation emitted. (in nm) -
## physics

A window air conditioner consumes 900 W of electric power and has COP = 2.9.If it runs continuously for 24 h , how much heat gets removed from the house? -
## Physics

A 52kg ice hockey player moving at 11m/s slows down and stops over a displacement os 8.0m. Calculate the net force of the skater. -
## physics

A rocket moves upward, starting from rest with an acceleration of 28.1 m/s2 for 4.76 s. It runs out of fuel at the end of the 4.76 s but does not stop. How high does it rise above the ground? -
## Physics

Suppose you wish to make a solenoid whose self-inductance is 1.2 mH. The inductor is to have a cross-sectional area of 1.2 10-3 m2 and a length of 0.048 m. How many turns of wire are needed? -
## physics

When a 1150 kg space rocket lifts off of ground. How many joules of energy has been provided by its engine during the time in which it achieves a speed of 180 m/s. -
## physics

a stone is projected vertically upward and reaches a maximum height of 20m before it returns to the thrower find the total time taken -
## Physics

Use the first law of thermodynamics to determine the amount of heat change, Q, and whther it was added to or removd from the system. W=225J Delta U=600J Q=? -
## physics

A ball of mass m is projected with a speed u at an angle theta with horizontol. Find the change in momentum after time t and when it reaches the ground -
## Physics

A monochromatic wavelength 600nm passed through a singlde slit which has a width of 0.8mm. A,calculate the distance between six and nineth bright frings. -
## physics

If the height of the water slide in the figure below is h1 = 1.55 m and h2 = 1.35 m, and the person's initial speed at point A is 0.593 m/s, at what location does the swimmer splash down in the pool? -
## Physics

What is the difference in blood pressure (mm−Hg) between the top of the head and bottom of the feet of a 1.82m tall person standing vertically? -
## Physics

Find the approximate gravitational red shift in 500 nm light emitted by a compact star whose mass is that of sun but whose radius is 10 km. -
## Physics

A group of students observes that a wooden block (m = 0.40 kg) on the end of a string with a radius of 0.7 meters makes 9 rotations in 20.7 seconds when twirled. -
## Physics

Find the approximate gravitational red shift in 500 nm light emitted by a compact star whose mass is that of sun but whose radius is 10 km. -
## physics

A group of students observes that a wooden block (m = 0.40 kg) on the end of a string with a radius of 0.7 meters makes 5 rotations in 20.7 seconds when twirled. -
## Physics

How long must a 25 degree ramp be to slow to a momentary stop a runaway truck moving along a truly horizontal highway at 85 miles per hour -
## physics

Determine the frequency and period for a pendulum of length 250cm, mass of 500g, and amplitude of 25cm I don't understand how to do this, help would be appreciated! Thank you -
## physics

A 1000 Kgs Vehicle moving with a sppeed of 20 meter per sec. is brought to rest in a distance of 50 metres. find the acceleration -
## physics

A novice skier, starting from rest, slides down a frictionless 33.0° incline whose vertical height is 127 m. How fast is she going when she reaches the bottom? -
## Physics

A weightlifter raises a 90k-g barbell from the floor to a height of 2/2 m in 0.6 s. What was his average power output during his lift? Sorry I wrote it wrong the first time! -
## Physics

Find the approximate gravitational red shift in 500 nm light emitted by a compact star whose mass is that of sun but whose radius is 10 km. -
## physics multiple choice MCQ 5- i need help please @all respective sir & bro

The unit of time in S.I. units is? a. second b. minute c. hour d. day e. year -
## physics

As a young boy swings a yo-yo parallel to the ground and above his head, the yo-yo has a centripetal acceleration of 250m/s^2. If the yo-yo's string is 0.50 m long, what is the yo-yo's tangential speed? -
## Physics

A 1.8 kg rectangular air mattress is 2.46 m long, 1.23 m wide, and 0.189 m thick. What mass can it support in water before sinking? Answer in units of kg. -
## physics

a small conducted sphere is attached to the end of an insulating rod .it carries a charge of +5.0*10-9 C. the plates ,which are 4.0 cm apart, are connected to a 50 000 V supply. -
## Physics

Calculate the magnetic flux density in air at a point 15mm from a long straight wire carrying a current of 100A -
## physics

A stone is thrown downward into a well with an initial speed of 5.00 m/s. The sound of splash is heard 1.50 s later. Find the depth of the well if the air temperature is 15.0 ˚C? -
## physics

A 58 kg skier has a speed of 9.5 m/s at point A. She then encounters a 1.75 m deep dip in the snow's surface that has a circular cross section with a radius of curvature of 12 m. -
## Physics/English/Nautical Mile

In my previous posts about the NM I think part of my problem is I do not understand the meaning of the word "SUBTENDED". Explanation please. Mike -
## physiçs

What precautions shouĺd i apply when doing a coefficieñt of friction.force applied to a blocķ on a hořizontal plane? -
## physics

two particles perform linear simple harmonic motionalongthe same path of length 2A and period T as shown in the graph below. the phase differe3nce between them is ------------- -
## Please help with Physics

I don't understand these questions. Give two examples of common force fields? How is the magnitude of an electric field defined? -I got that it is its strength -
## Physics please help!

Suppose you wish to make a solenoid whose self-inductance is 1.2 mH. The inductor is to have a cross-sectional area of 1.2 10-3 m2 and a length of 0.048 m. How many turns of wire are needed? -
## Physics

Rotating initially at 1800 rpm, a wheel with a diameter of 74.0 cm is brought to rest in 11.0 s. Calculate the magnitude of its angular acceleration in radians/second^2 -
## PHYSICS

What is the angular momentum of a 2.7 kg uniform cylindrical grinding wheel of radius 12 cm when rotating at 1600 rpm? How much torque is required to stop it in 4.4 s? -
## physics

What is the smallest radius of an unbanked (flat) track around which a bicyclist can travel if her speed is 31 km/h and the coefficient of static friction between the tires and the road is 0.29? -
## physics

If 4.5 kg object is sitting at rest on a 30 degree incline that has a coefficient of static friction of .19, what is the net force down the plane? Does it start sliding? -
## Physics

Calculate the components parallel and perpendicular to the plane of 150N gravitational force acting on an object on a slope at 20 degrees to the horizontal ? -
## physics

An old-fashioned single-play vinyl record rotates on a turntable at 46.0 rpm. What are (a) the angular velocity in rad/s and (b) the period of the motion? -
## Physics

A 21.0 kg child descends a slide 3.4 m high and reaches the bottom with a speed of 2.0 m/s. How much thermal energy due to friction was generated in this process? -
## physics

Two eagles fly directly toward one another, the first at 15.0 m/s and the second at 21.0 m/s. Both screech, one emitting a frequency of 3200 Hz and the other one of 3800 Hz. What frequencies do they receive if the speed of sound is 330 m/s? -
## physics

an experimental jetplane just after takeoff climbs with a speed of 500km/hr at an angle of 37 degrees with the horizontal. At what rate is the plane gaining altitude? -
## physics

an astronaut is competing in mars olympic game her mass is 50 kg she will drive from tower 17 mm above a pool of water how much work in nj must she do to climb 17m -
## Physics

Ahmad throws a ball straight up. For which situation is the vertical velocity zero? [Note: Neglect the air resistance] Answer at the top on the way up none of the above on the way down -
## physics

A referee tosses a coin straight up with a velocity of 5.25 m/s, how high does it go above its point of release? (Hint: How fast is it moving at the maximum height?) -
## Physics

A monoatomic gas expands isobarically.What will be the percentage of heat supplied that increases the thermal energy and that involved in doing work for expansion? -
## physics

at what inclination should the object be released from rest if it is to reach a maximum horizontal distance of 2m as shown. coeff of friction is 0.37 for all surfaces of contact. -
## Physics

Calculate the force exerted on a rocket, given that the propelling gases are expelled at a rate of 1800 kg/s with a speed of 3.8×104 m/s (at the moment of takeoff). -
## Physics

How does the cochlea sense sound? •Snail shaped tube lined with receptor cells which transmits signals to the brain. Correct? -
## physics

Two eagles fly directly toward one another, the first at 15.0 m/s and the second at 23.0 m/s. Both screech, one emitting a frequency of 2600 Hz and the other one of 3800 Hz. What frequencies do they receive if the speed of sound is 330 m/s? -
## Physics

8kg mass moving with a speed of 30 of 30ms-1 is brought to rest in 2.5sec, calculate the magnitude of the constant retarding force -
## physics

An automobile manufacturer claims that its product will travel 1.2 km in 27 s, starting from rest. What is the magnitude of the constant ac- celeration required to do this? Answer in units of m/s2. -
## Physics

A roller-coaster car is moving at 20.0 m/s along a straight horizontal track. What is its speed after climbing a 15.0 m hill? Neglect the effects of friction. -
## Physics

If it takes 5 seconds for the baseball to fall, how far from the tower will it land? I used vertical distance formula dy=1/2(g)t^2 and got 122.5 but its one of the answers in the multiple choice. Please help. -
## physics

Frosty the Snowman was a jolly happy soul of mass 85 kg. If his initial temperature was -19C , how much heat did he absorb till he was at 25C ? -
## Physics

A rocket moves upward, starting from rest with an acceleration of 34.4 m/s2 for 4.40 s. It runs out of fuel at the end of the 4.40 s but does not stop. How high does it rise above the ground? -
## Physics

If a freely falling rock were equipped with a speedometer, by how much would its speed readings increase with each second IF it were on a planet where g = 20 m/s2? Show all work leading to your answer. g=20 m/s^2 20 m/s V=gt S=g( T ^2) / 2 Is this right ? -
## Physics

Determine lamda m Oments wavelength of the peak of the Planck distribution annd the corresponding frequency f at these temperature a) 3.00k. b)300k c)3000k -
## Physics

Two identical balls roll off the edge of a horizontal table top. One leaves traveling at twice the speed of the other. Which ball hits the floor first? Why? -
## physics

A circular swimming pool has a flat bottom and a 4.39 m diameter. It is filled with water to a depth of 1.51 m. There is 1.36 atm of pressure on the top surface. -
## physics

The radius of a merry-go-round is 7 meters, and it takes 12 seconds to make a complete revolution. What is the speed of an atom on the outer rim? -
## Physics

I need to explain and demonstrate mathematically why it is easier to pull a wheelbarrow than it is to push it. Also, what effect does the component of force parallel to a bicycle crank have? -
## physics

a long jumper takes off at an angle of 20 degrees with the horizontal and reaches a maximum height of 0.55 meters at mid- flight. how far did she jump? -
## Physics

Your electric jug element produces 1.5kW of power. What is the minimum time it will take to heat 1.5L of water from 20 degrees Celcius to boiling -
## physics

Two eagles fly directly toward one another, the first at 15.0 m/s and the second at 21.0 m/s. Both screech, one emitting a frequency of 3200 Hz and the other one of 3800 Hz. What frequencies do they receive if the speed of sound is 330 m/s? -
## Quantum Physics

Suppose a particle has wavefunction ψ(x,t=0)=Aexp(−x22l2). What is the average value (expectation value) of p^, ⟨p^⟩, for this state at t=0? -
## Physics

I need to explain and demonstrate mathematically why it is easier to pull a wheelbarrow than it is to push it. Also, what effect does the component of force parallel to a bicycle crank have? -
## Physics

Steve can paddle his canoe at 10 km/h in still water. If he paddles directly against a river’s current that is moving at 3 km/h, what is Sam’s velocity relative to the shoreline? -
## Physics

In the following diagram there is a coefficient of friction, μ, of 0.15 between the 5.0 kg mass and the surface. Calculate the tension in the cable connecting the two masses and the resulting acceleration. -
## physics

Two eagles fly directly toward one another, the first at 15.0 m/s and the second at 21.0 m/s. Both screech, one emitting a frequency of 3200 Hz and the other one of 3800 Hz. What frequencies do they receive if the speed of sound is 330 m/s? -
## physics

a point mass of 12.5 kg is hung from an 18.3 m long rope and swings back and forth with an amplitude of 2.34m. what is the oscillation period for the pendulum system? -
## College Physics

Construct & solve a problem involving a person swimming across a river which has a waterfall some distance downstream. Please help, I have no idea where to start. -
## Physics

By what amount will a 178 m long concrete slab on the Mackinac Bridge contract when going from +39C to -35C? The linear expansion coefficient is 10^-5 per C. -
## Physics

When tossed upward and hit horizontally by a batter, a 0.23 kg softball receives an impulse of 2.0 N·s. With what horizontal speed does the ball move away from the bat? -
## Physics

Need help with a question! I worked out A (assuming its right) which leads to B. A) C=1.03x10^-4 uF, A=2.5mm^2, d=0.75um B) If the voltage across the membrane is delta V= 75mV, what is the charge +_Q on each surface A? thanks! -
## Physics Problem 6.9

Four 8.5 kg spheres are located at the corners of a square of side 0.56 m Calculate the magnitude and direction of the gravitational force on one sphere due to the other three? -
## PHYSICS

In an archery practice an arrow was realesed from a bow with a velocity of 20m/s it strikes and slopes find at what rate the aarrow was aaccelarated -
## Physics

I have a spring on a horizontal frictionless surface. Initially it is un-stretched and at x = 0 cm. I then pull it back 10 cm and release it. What is the amplitude of the oscillations (the object has mass m)? -
## physics

Qualitatively explain how you would expect the potential energy to change as a glider slides down an inclined air track, where friction is negligible. -
## physics

if you wished to warm 100 kg of water by 15 degrees celsius for your bath, how much heat would be required? (give your answer in calories and joules) -
## Physics 1

What is the minimum speed a 3,200 pound car can have on a flat road when going around a curve with a radius of 300ft. Take the static coefficient of friction to be 0.8. -
## physics

A Martian rover is moving up a hill sloped at 30.0° with the horizontal. If it has a constant velocity of 1.50 meters/second, calculate its vertical displacement after 21.0 seconds. -
## Chemistry/Physics

When 1mol of a gas burns at constant pressure, it produces 2430J of heat and does 5kJ of work. Calculate change in H, q, and in kJ? -
## Physics: Fluids

A sample of an unknown material weighs 260 N in air and 175 N when immersed in alcohol of specific gravity 0.700. -
## physics

A football player is running at a speed of 9m/s hits the goalpost and comes to a stop in 0.050 sec. Calculate his acceleration and compare it with that of gravity. -
## Physics

Electrons are ejected from a photoelectric cell with a maximum kinetic energy of 1.20 eV. If the incident light has a wavelength of 410nm, what is the work funtion? -
## physics

What is the required resistance of an immersion heater that will melt 6.39 kg of ice at 0°C in 36 min while operating at 110 V? im not too sure how to do this because delta_T=0. With the equations im using, i get 0 but its not the answer and im not quite -
## physics

An outfielder throws a 0.150-kg baseball at a speed of 50.0 m/s and an initial angle of 30.0°. What is the kinetic energy of the ball at the highest point of its motion? -
## Physics

A train moving with constant speed of 54kmph moves eastwards for 30min then north for 40min find avg velocity -
## physics

An 8 hour exposure to a sound level of 95.0 dB may cause hearing damage. What energy in joules falls on a 0.850 cm diameter eardrum so exposed? -
## physics

A ball is thrown straight up with an initial speed of 60 m/s. How high does it go? Assume the accelera- tion of gravity is 10 m/s22 2)How long is it in the air? -
## physics

Find the approximate gravitational red shift in 500 nm light emitted by a compact star whose mass is that of sun but whose radius is 10 km. -
## PHYSICS

3 PARTICLES OF MASS 1KG,2KG,3KG PLACED AT CORNER A,B,C OF AN EQUILARERA TRIANGLE A,B AND C.LOCATE THE POSITION OF PARTICLE/FIND COORDINATES