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Physics: Speakers A & B are vibrating in phase; what is the distance?

Speakers A and B are vibrating in phase. They are directly facing each other, are 7.80 m apart, and are eack playing a 73.0-Hz tone. The speed of sound is 343 m/s. On the line between the speakers there are three points where constructive interference occurs. What are the distance of these three points from speaker A?

Finding the ratio between two velocities down a ramp.

A marble and a cube are placed at the top of a ramp. Starting from rest at the same height, the marble rolls and the cube slides (no kinetic friction) down the ramp. Find the ratio of the center-of-mass speed of the cube to the center-of-mass speed of the marble at the bottom of the ramp.

Speed of a bullet measured using ballistic pendulum !

A simple way to measure the speed of a bullet is with a ballistic pendulum. This consists of a wooden block mass, M, into which the bullet mass, m, is shot. The block is suspended from cables of length, l, and the impact of the bullet causes it to swing through a maximum angle, A. The initial speed of the bullet is v. a) How

Mechanics: moment of inertia, projectiles

1)a.A grind stone of 0.1m thick,1m of diameter and a relative density of 2.53 find-moment of inertia+ radius of gyration. b)A gun is fired at a target 12km away at an angle of 35deg and hits target.How long is the projectile in the air and what's it's velocity? need complete step by step answer,thanks..

Instantaneous Velocity Problem

The position of a particle moving on an x axis is given by: x=7.8 + 9.2t - 2.1t^3 with x in meters and t in seconds. What is its velocity at t=3.5s? Is velocity constant or changing?

Physics Problems Kinematics, Acceleration

Show all steps in computation. 1) A VW RAbbit can go from rest to 80.5 km/h (50.0 mi/h) in a modest 8.20 s. How long will it take to speed from 48.3 km/h to 64.4 km/h, along a straight run, if the average acceleration is the same as before? 2)During a takeoff a small plane has an average tangential acceleration of 5.0 m/s^2

Working with integration

The velocity of a particle moving in a straight line is given by v=3t^2 + 2t, Find an expression for the displacement at time, t. If the initial displacement is 1m, find an expression for the constant of integration. Hence determine the displacement after a time period of 2s has elapsed.

Projectile motion

A bullet fired horizontally is aiming at an object which starts falling at the instant the bullet is fired. Will the bullet hit the object ?

Using differentiation to describe the motion of an object launched upwards.

Questions are taken from the course book 'Physics with modern physics', Richard Wolfson & J. M. Pasachoff. A model rocket is launched straight upward; its altitude as a function of time is given by y = bt-ct^2, where b=68 m/s, c=4.9 m/s, t is the time in seconds, and y is in meters. (a) Use differentiation to find a ge