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    Electric Field and Electric Potential Question

    Homework Statement You have a Square with 10cm lengths on each side. Charges of +4 microC (top right corner), -6 microC (top left corner), and +4 microC (bottom left corner) are located at three corners of the square. A) Calculate the electric field in the empty corner of the square. B)...
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    Light after a Polarizer Question

    Homework Statement Initially unpolarized light with an intensity of 240W/m2 is incident on a series of two polarizers. What should be the angle between to the axes of the two polarizers such that the transmitted intensity after the second polarizer is 37.5% of the incident one? Homework...
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    Relativity Question

    Homework Statement A) at what velocity will be the KE of a spaceship 2/3 of its rest energy? B) If the Spaceship travels at this velocity relative to the earth and its trip takes 10 years as measured in the earthbound system, how much time has elapsed on the spaceship clock? C) What is the...
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    Double Slit Interference Question

    Homework Statement Light of wavelength 680 nm falls on two slits and produces an interference pattern in which thefourth-order fringe is 38 mm from the central fringe on a screen 2.0 m away. What is the separationof the two slits? Homework Equations Sintheta=2m(\lambda2d)...
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    Lens Combination Question.

    Homework Statement Two 28.0-cm-focal-length converging lenses are placed 16.5 cm apart. An object is placed 36.0 cm in front of one lens. Where will the final image be formed by the second lens? Homework Equations 1/do + 1/di = 1/f The Attempt at a Solution for the first...
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    Converging Lens Problem

    Homework Statement (a)How far from a 50.0-mm-focal-length lens must an object beplaced if its image is to be magnified 2.00 x and be real? (b)What if the image is to be virtual and magnified 2.00x? Homework Equations m = -di/do 1/do+ 1/di = 1/f The Attempt at a Solution m...
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    Optics: 2 lens problem

    Homework Statement We have a convex lens with a focal length of 8cm, which is 12cm from the second converging lens that has a focal length of 4cm. An object is 12cm from the first lens. Where is the final image? Homework Equations 1/do + 1/di = 1/f The Attempt at a Solution So...
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    Sinusoidal in time

    Hi, I having trouble grasping what: "oscillatory motions are sinusoidal in time" means... does this just mean that when solving a problem for simple harmonic motion that the equation is going to involve both and sin/cos and time? Sorry this might be more of a mathematical question.
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    Newtons Law and Friction Question (along with a contact force question)

    Homework Statement Two crates, of mass 75 kg and 110 kg are in contact and at rest on a horizontal surface. A 620N force is exerted on the 75 kg crate. If the coefficient of kinetic friction is 0.15 calculate: a) the acceleration of the system b)the force that each crate exerts on the...
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    Find the Net Force and Acceleration Question

    Homework Statement The two forces F1 and F2 (shown in the figure) (i attached the figure hopefully I did it correctly) act on a 27.0 kg object on a frictionless tabletop. If F1=10.2N and F2= 16.0N, find the net force on the object and its acceleration for a and b Homework Equations...
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    Motion driven by force

    the motion of a body is always in the direction of the resultant force. Why wouldn't this be a correct statement? I thought all the forces on a body were added up and the resultant force was the direction in which the body moved. Am I confusing net force with resultant force? I was under...
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    Projectile Motion Firing Question

    Homework Statement A projectile is fired with an initial speed of 65.2m/s at an angle of 34.5deg above the horizontal on a long flat firing range. Determine (a) the maximum height reached by the projectile, (b) the total time in the air, (c) the total horizontal distance covered (that is...
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    Projectile Motion Angles Question

    Homework Statement A fire hose held near the ground shoots water at a speed of 6.8m/s. At what angle(s) should the nozzle point in order that the water land 2.0m away? Why are there two different angles? Homework Equations v = v(initial) +at x = x(initial) + v(initial)t + .5at^2...
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    Question about displacement

    Hi, Sorry about the question, as I'm sure its super simple, I'm new to physics :) If I'm running a on a circular track and I do say 4 laps (1/4 mile each lap, 1 mile total) is my displacement equal to 0. Since I ended the run exactly where I started? Thanks for the help!
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    One Dimension Kinematics Question

    Homework Statement A fugitive tries to hop a freight train traveling at a constant speed of 6.0 m/s. Just as an empty box car passes him, the fugitive starts from rest and accelerates at a=4.0 m/s2 to his maximum speed of 8.0 m/s. (a) How long does it take him to catch up to the empty box...
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    Textbook recommendations for General Physics I

    Sorry if this topic has been covered before or if I'm posting it in the wrong section. I'm new to the forum. I am about to start General Physics 1 this summer (start date June 3rd) and was wondering if anyone had any recommendations for additional textbooks to purchase that could really help...