Explore BrainMass

Classical Mechanics

Mixed Algebra & Calculus Problems

(See attached files for full problem descriptions) --- Problem Set 1 1) If 2x + y = 3 and x - y = 3: a) What is x? A) 1 B) 2 C) 3 D) 0 E)-1 b) What is y? A) 1 B) 2 C) 3 D) 0 E)-1 2) If you walk 3 miles in one hour and then 4 miles in two hours, what is your average speed for the entire trip? (in mph

Energy of pulse on a string

Here is a string problem I'm having much trouble with. An explanation would be greatly appreciated. It's written much more clearly on the attachment, so please go there first!!! Here it is, Consider a string under a tension T, mass density ρ with a pulse ξ(x,t) = ξ_0^ (-(x-ct)^2/a^2) . propag

Maximum load of a raft

A raft is constructed of wood having density 600kg/m^3. Its surface area is 5.8m^2 has a thickness of 12 cm. Find the maximum load the raft can carry on it without sinking. (density of water 100kg/m^3)

Fluids Cross-Sectional Area

In the hydraulic lift the red piston has a cross-sectional area of 0.69 m2 and the green piston a cross-sectional area of 0.06 m2 and the force F1 = 176 N. What weight to the nearest newton can this configuration lift? If the green piston is depressed 0.67 meters, how far up would the red piston move to the nearest thousandth

Speed, time, distance

Bobby traveled a distance of 50x+150 miles at 50 miles per hour on the Gulf Freeway. Find a binomial that represents the time that he traveled.

Mass comparison problem

Two objects have the same kinetic energy. if the first object is moving 3 times faster than the second object, what is the second object's mass in comparison to the first object's mass?

Coordinates of the Center of Mass

The coordinates of three particles are (5, 7), (0, 3), and (-1,-1). If the three particles have masses of 1.0 kg, 2.0 kg and 2.0 kg respectively, what are the coordinates of the center of mass?

Oscillation and Pendulum Motion

A mass on a string of unknown length oscillates as a pendulum with a period of 4.0 (s). Parts a to d are independent questions, each referring to the initial situation. What is the period if: a. The mass is doubled? in seconds b. The string length is doubled? in seconds c. The string length is halved? in seconds d. The ampli

Classical mechanics problems

(See attached file for full problem description) Please change the file extension to *.doc so that it can be open by Word. 15. A ball of mass 0.5 kg, initially at rest, acquires a speed of 4 m/s immediately after being kicked by a force of strength 20N... 16. A wooden block of mass M is moving at speed V in a straight l

Impulse with Constant Velocity

An 79.1 kg astronaut is working on the engines of his ship, which is drifting through space with a constant velocity. The astronaut, wishing to get a better view of the Universe, pushes against the ship and much later finds himself 30.4 m behind the ship. Without a thruster, the only way to return to the ship is to throw his 0.5

Mechanics and Projectile Motion

Please help with these two mechanics questions: 1. A punter kicks a football at an angle of 33.1 degrees with the horizontal at an initial speed of 24.5 m/s. What distance (in meters) away should a punt returner position himself to catch the ball just before it strikes the ground? And to what vertical height (in meters) does t

Force and Tension

A tightly stretched "high wire" is 42.8 m long. It sags 3.5 m when a 63.8 kg tightrope walker stands at its center. What is the tension in the wire?

Current, magnitude

A solenoid 12 cm long has a total of 10,000 turns of wire uniformly distributed along its length. It carries a current of 0.833 A and is filled with a ferromagnetic material with a permeability 700 times the permeability of free space What is the magnitude of B at the center?

Tension in a sphere

A spherical shaped hollow steel shell with a radius of 2.5 m containing some instruments is lowerd by a cable into a lake the shell with its contents weighs 7.5*10^5N on the deck of the ship wich is being lowered. What is the tension in the cable when the sphere is completly immersed in the water?

Kinetic friction

If an object slides directly down an inclined place, at a constant velocity of 6 m/s, how large is the coefficient of kinetic friction if the plane make an angle of 25 degrees with the horizontal?

Finding Wavelength and Amplitude

A wave travels along a stretched rope. The vertical distance from crest to trough for this wave is 17 cm and the horizontal distance from crest to trough is 23 cm. What is: (a) the wavelength and (b) the amplitude of this wave?

Solve: Distance and Time

Hi, I need some assistance with the following questions: Question: At the average rate of 15 m/s^2. How much time does it take for the complete increase in speed? a. 0.25 s b. 4.0 s c. 0.0577 s d. 17.3 s e. 8.0 s Question: A car traveling 20 m/s is able to stop in a distance d. Assuming the same braking force, what

A 200 g object is moving in a circle of radius 4.0 m a

A 200 g object is moving in a circle of radius 4.0 m a uniform speed of 6.0 m/s. the net force acting on the object is: a. 3.6 N towards the center of the circle b. 3.6 N tangential to the circle c 1.8 towards the center of the circle d. 1.8 N away from the center 0f the circle

Two objects have the same kinetic energy. if the

Two objects have the same kinetic energy. if the object is moving 3 times faster than second object, what is the second object's mass in comparison to the first object's mass? a. 3 times larger b. it is the same c. 9 times larger d. can not determine

A cylindrical specimen of steel

A cylindrical specimen of steel of cross sectional area 5 cm^2 is subjected to a tensile force of 800 N. the stress in material is a. 8.0 * 10^3 N/m^2 b 4.0 * 10^3 N/m^2 c. 1.6 * 10^6 N/m^2 d. 3.2 *10^6 N/m^2

A safe

A safe with a mass of 150kg is at rest on the floor. what is the minimum horizontal force needed to move the safe if the coefficent of static friction between the safe and the floor is 0.3? a.441n b. 51n c.501n d.41n

Simple Harmonic Motion.

I have to find the mass of an object. The problem is that my result is a negative one. The problem is as follows: A teacher demonstrates a harmonic motion with an object of mass m0, hung on a wire with constant k. A mass of 1,25g is added to the object, which results in a loss of 2.5% of the original frequency. What is the

Multiple choice question on elongation of wire

The weight that will cause a wire of diameter d to stretch a given distance, for a fixed length of wire, is a. proportional to d^2 b. independant of d c. proportional to d d. independant of what the lengthof wire is


What is a pulley? where is it used?