Physics Homework Help

An object is 2.3 cm tall, and 5.5 cm from a converging lens.  The image is upright and 9.0 cm tall.  What is the focal length of the lens?

Posted by lkehoe May 19, 2013 at 5:52 AM via web. 1 educator answer. »

Light enters a substance from air at 45.0 degrees to the normal.  It continues through the substance at 34.7 degrees to the normal.  What...

Posted by lkehoe May 19, 2013 at 5:47 AM via web. 1 educator answer. »

An optic fiber is made of clear plastic with index of refraction of 1.50.  For what angles of incidence will light remain within the plastic?

Posted by lkehoe May 19, 2013 at 5:45 AM via web. 1 educator answer. »

Light is passing through a transparent material at an angle of 63 degrees.  The material has an index of refraction of 1.6.  At what angle...

Posted by lkehoe May 19, 2013 at 5:43 AM via web. 1 educator answer. »

A +35 "mu"C point charge is placed 32 cm from an identical +35 "mu"C charge. What is the electric potential at the point midway between the...

Posted by lkehoe May 13, 2013 at 4:54 PM via web. 2 educator answers. »

A particle with a charge of 4.0 "mu"C has a mass of 5.0 x 10^-3 kg.  What electric field directed upward will exactly balance the weight of...

Posted by lkehoe May 13, 2013 at 4:47 PM via web. 1 educator answer. »

The force between a 40 "mu"C charge and a  -50 "mu"C charge is 2.3 N.  How far apart are they?`mu`

Posted by lkehoe May 13, 2013 at 4:45 PM via web. 1 educator answer. »

A 75 nC charge is 8.0 m from a second charge, and the force between them is 1.0 N.  What is the magnitude of the second charge?

Posted by lkehoe May 13, 2013 at 4:30 PM via web. 1 educator answer. »

A foam ball of mass 0.150 g carries a charge of -2.00 nC.  The ball is placed inside a uniform electric field, and is suspended against the...

Posted by lkehoe May 13, 2013 at 4:28 PM via web. 1 educator answer. »

A uniform electric field of 50 V/m is directed toward the east.  If the voltage measured relative to ground at a given point is 80 V, what is...

Posted by lkehoe April 30, 2013 at 5:14 AM via web. 1 educator answer. »

A parallel-plate capacitor consistsof plates of area 1.5 x 10^-4  m^2. And separated by 1.0 mm.  The capacitor is connected to a 12 -V...

Posted by lkehoe April 30, 2013 at 5:10 AM via web. 1 educator answer. »

An 80 mm focal-length lens is used to focus an image for a camera, a) how far is the image from the lens if the object to be photographed is...

Posted by lkehoe April 27, 2013 at 8:49 PM via web. 1 educator answer. »

An object is 2.3 cm tall, and 5.5 cm from a converging lens.  The image is upright and 9.0 cm tall.  What is the focal length of the lens?...

Posted by lkehoe April 27, 2013 at 8:43 PM via web. 1 educator answer. »

An optic fiber is made of clear plastic with index of refraction of 1.50.  For what angles of incidence will light remain within the plastic?

Posted by lkehoe April 27, 2013 at 8:40 PM via web. 1 educator answer. »

Light enters a substance from air at 45 degrees to the normal.  It continues through the substance at 34.7 degrees to the normal. What would...

Posted by lkehoe April 24, 2013 at 11:35 PM via web. 1 educator answer. »

Light is passing through a transparent material at an angle of 63 degrees.  The material has an index of refraction of 1.6.  At what angle...

Posted by lkehoe April 24, 2013 at 11:15 PM via web. 1 educator answer. »

Light enters a substance from air at an angle of 32 degrees, and continues at an angle of 23 degrees.  What is the index of refraction of the...

Posted by lkehoe April 24, 2013 at 11:00 PM via web. 1 educator answer. »

If a material has an index of refraction of 2.25, what is the speed of light through it?

Posted by lkehoe April 24, 2013 at 10:53 PM via web. 1 educator answer. »

An electron acquires 7.45 x 10^-17 J of kinetic energy when it is accelerated by an electric field from plate A to plate B.  (a) What is the...

Posted by lkehoe April 22, 2013 at 6:24 PM via web. 1 educator answer. »

How much kinetic energy will an electron gain (in joules and eV) if it accelerates through a potential difference of 23,000 V in a TV picture...

Posted by lkehoe April 22, 2013 at 6:21 PM via web. 1 educator answer. »

How much work does the electric field do in moving a proton from a point with a potential of +125 V to a point where it is -55.0 V? Express...

Posted by lkehoe April 22, 2013 at 6:19 PM via web. 1 educator answer. »

How much work does the electric field do in moving a -7.7 `muC` charge from ground to a point where potential is +55 V higher? 

Posted by lkehoe April 22, 2013 at 6:17 PM via web. 1 educator answer. »

The cross-section area of an adjustable single loop is reduced from 1.2 m^2 to 0.4 m^2 in 0.25 seconds.  What is the average emf that is...

Posted by lkehoe April 15, 2013 at 6:38 PM via web. 1 educator answer. »

A uniform 1.5 T magnetic field points north.  If an electron moves vertically downward (toward the ground) with a speed of 2.5 x 10^7 m/s...

Posted by lkehoe April 15, 2013 at 6:35 PM via web. 1 educator answer. »

The cross-sectional area of an adjustable single loop is reduced from 1.2 m^2 to 0.40 m^2 in 0.25 seconds.  What is the average emf that is...

Posted by lkehoe April 15, 2013 at 6:32 PM via web. 1 educator answer. »

A high power line carrying 1000 A generates what magnetic field at the ground, 10 m away?

Posted by lkehoe April 15, 2013 at 6:29 PM via web. 1 educator answer. »

A 2.0 m wire carrying a current of 0.60 A is oriented parallel to a uniform magnetic field of 0.50 T.   (a) What is the magnitude of the...

Posted by lkehoe April 15, 2013 at 6:28 PM via web. 1 educator answer. »

The magnetic flux through a coil of wire with two loops has a charge of 88 Wb in 0.42 seconds.  What is the magnitude of the emf induced in...

Posted by lkehoe April 14, 2013 at 4:29 PM via web. 1 educator answer. »

A 256 turn coil with a cross sectional area of 0.0025m^2 is placed in a uniform external magnetic field of strength 0.25 T so that the plane...

Posted by lkehoe April 11, 2013 at 9:33 PM via web. 1 educator answer. »

A 12,0 -cm-diameter loop of wire is initially oriented perpendicular to a 1.5 T magnetic field.  (a) Find the magnetic flux through the loop....

Posted by lkehoe April 11, 2013 at 9:20 PM via web. 1 educator answer. »

A single circular loop with a radius of 22 cm is placed in a uniform external magnetic field with a strength of 0.50 T so that the plane of...

Posted by lkehoe April 11, 2013 at 8:26 PM via web. 1 educator answer. »

At what distance from a long straight wire carrying a current of 5.0 Amps is the magnitude of the magnetic field due to the wire equal to the...

Posted by lkehoe April 9, 2013 at 11:35 PM via web. 1 educator answer. »

If an electric wire is allowed to produce a magnetic field no larger than that of earth (5.5 x 10^-5 T) at a distance of 25 cm, what is the...

Posted by lkehoe April 9, 2013 at 11:25 PM via web. 2 educator answers. »

A wire of length 55.5 cm carrying 8.75 Amps flows through a uniform magnetic field. The wire experiences a maximum force of 1.28 N toward the...

Posted by lkehoe April 9, 2013 at 11:06 PM via web. 1 educator answer. »

How much current is flowing in a wire 4.8 m long if the maximum force on it is 0.75 N when placed in a uniform 0.08 T field?  

Posted by lkehoe April 9, 2013 at 10:53 PM via web. 1 educator answer. »

Can you show how to calculate the magnitude of the magnetic force  on a 160 meter length of straight wire stretched between two towers...

Posted by lkehoe April 9, 2013 at 10:47 PM via web. 1 educator answer. »

If the electricity delivered to a factory is at 50,000 Volts, What is the current use and the power dissipated in the wires at 50,000 Volts?  

Posted by lkehoe April 3, 2013 at 4:29 AM via web. 2 educator answers. »

A power station delivers 600 kW of power at 12,000 V to a factory.  What current is required to deliver this power The wires from the power...

Posted by lkehoe April 3, 2013 at 4:26 AM via web. 1 educator answer. »

Consider two copper wires.  One has twice the length of the other.  How do the resistivities of these two wires compare?

Posted by lkehoe April 3, 2013 at 2:34 AM via web. 1 educator answer. »

What are the websites to buy project materials like propellers, motors, resistors etc in India in Cash on Delivery?Nothing

Posted by astrosonuthird February 13, 2013 at 3:57 PM via web. Be the first to answer. »

Question on point charge particles in a squareTwo pos. and two neg. point particles, all with charge of magnitude q =  5nC,  are placed at...

Posted by aarhish February 8, 2013 at 2:00 AM via web. 1 educator answer. »

An object is dropped from a height of 26.8 m. What is its average acceleration (assumed to be constant) if it hits the ground with a speed of...

Posted by quietbang February 4, 2013 at 6:27 PM via web. 1 educator answer. »

A canoe has a velocity of 0.40m/s southeast relative to the earth. The canoe is on a river that is flowing 0.50m/s east. Find the velocity...A...

Posted by filabr-2 January 31, 2013 at 8:57 PM via web. 1 educator answer. »

If a person glides through the air at a height of 215 m with a velocity of 25.4 m/s, suddenly they dive to a height of 178 m.  What is the...

Posted by lkehoe January 27, 2013 at 10:04 PM via web. 1 educator answer. »

If a person glides through the air at a height of 215 m with a velocity of 25.4 m/s, suddenly they dive to a height of 178m.  Whats the new...

Posted by lkehoe January 27, 2013 at 10:02 PM via web. 1 educator answer. »

A 4357 kg roller coaster starts from rest at the top of a 36.5 m high track. Determine its speed of the car at the top of a loop that is 10.8...

Posted by lkehoe January 27, 2013 at 9:37 PM via web. 1 educator answer. »

What is position of particle?the particle have position of vector u=p8vector a+r*vector b vector a = i+j vectorb=i-j vector u=6i+2j

Posted by user6867744 January 5, 2013 at 6:49 PM via web. Be the first to answer. »

Structure of socket ball - Harvard???http://www.youtube.com/watch?v=-i2jvVoxqFg  

Posted by ttkjemsj December 20, 2012 at 8:48 AM via web. Be the first to answer. »

What is diffraction?How is it done? Its mechanism.......

Posted by astrosonuthird December 18, 2012 at 12:50 PM via web. 1 educator answer. »

what is time dilation ?

Posted by somakc December 15, 2012 at 1:39 PM via web. Be the first to answer. »