Explore BrainMass


Roller Coaster Physics

ROLLER COASTER DESIGN Designing a roler coaster is very tricky. Patrons of theme and amusement parks want to be thrilled , but generally do not want to be injured. Downard accelerations of greater than 10 g cause bodily harm. Negative (i.e upward) accelerations of greater than about 5 g also cause damage ( "red out") The

Distance Calculations

80. To go to a football stadium from your house, you first drive 1000 m north, then 500 m west, and finally 1500 m south. (a) Relative to your home, the football stadium is (1) north of west, (2) south of east, (3) north of east, or (4) south of west. (b) What is the straight-line distance from your house to the stadium? 8

Roller Coaster Work Problem

The questions refer to the roller coaster in the diagram (attached). The mass of the roller coaster, including passengers = 500 kg. Assume that friction and drag forces are so small they can be ignored. 1. Measured from "ground level," what is the gravitational potential energy of the roller coaster at the top of the first hi

Force and potential energy and work

Please give complete solutions. Thanks! A spring-loaded dart gun shoots a dart with a mass of 150 grams. The spring constant of the dart gun is 4000 N/m, and when the dart is placed in the gun, the spring is compressed 15 cm (See attachment for the rest).

Forces and Free Body Diagrams

1. The kinetic energy of a car moving at 30km/h is 2MJ. When the car is moving at 90km/h, what is the kinetic energy? 2. A brick falls off a ledge 30 meters above the ground. An identical brick falls off another ledge 60 meters high. What can you say about the kinetic energies of the bricks, if you compare their kinetic energ

Please, find the anwer and show me how you got it if you can

1>What is the electric potential at a point 0.45 m away from a point charge of a of 2.5mC 2> If 3.75 X 10^-4 J of work are required to move 13.7 microc of charge from one point to another, what is the electric potentail difference the two points. 3> An electron is released from rest in a vacumm between two flat, parallel

Calculating Mass of a Sphere

1) Grains of fine beach sand are assumed to be spheres of radius 57.5 micro meters. These grains are made of silicon dioxide which has a density of 2600kg/m^3. What is the mass of each grain of sand and answer in kg. Got answer of 2.1 * 10^-9 kg from previous work, but wrong answer. Please step by step help work this o

Micro-F Capacitor

Hi. Can someone please check these two answers? (a) seems very low and (b) seems very high to me. A 0.22 micro-F capacitor is charged by a 1.5-V battery. After being charged, the capacitor is connected to a small electric motor. Assuming 100% efficiency, (a) to what height can the motor lift a 5.0-g mass? (b) What initial vol

Fluids, Pressure and Depth

A patient is to receive an intravenous injection of medication. In order to work properly, the pressure of fluid containing the medication must be 109 kPa at the injection point. (a) If the fluid has a density of 1020 kg/m^3, find the height at which the bag of fluid must be suspended above the patient. Assume that the pressure

Laws of Motion/Free Fall

Question: When baseball players throw the ball in from the outfield, they usually allow it to take one bounce before it reaches the infield, on the theory that the ball arrives sooner that way. Suppose that the angle at which a bounced ball leaves the ground is the same as the angle at which the outfielder threw it, but that the

Classical Physics Problems

1. During a rockslide, a 520 kg rock slides from rest down a hillside that is 500m long and 300m high. The coefficient of kinetic friction between the rock and the hill surface is 0.25 (a) If the gravitational potential energy U of the rock-Earth system is zero at the bottom of the hill, what is the value of U just before the

The Conservation of Energy

A skier coasts down a very smooth, 10-m-high slope (v =20 m/s), what is his speed at the bottom of the slope. If the skier has a mass of 60kg and the force of friction retards his motion by doing 2500 j of work, what is his speed at the bottom of the slope?

Spring constant problem: Work done, speed of block, maximum compression

A 230 g block is dropped onto a relaxed vertical spring that has a spring constant of k = 2.5 N/cm (Fig. 7-30). The block becomes attached to the spring and compresses the spring 14 cm before momentarily stopping. What work is done on the block by the spring force while the spring is being compressed? (in J) What is the s

Strength of a fishing line

1. The tension at which a fishing line snaps is commonly called the line's "strength." What minimum strength is needed for a line that is to stop a salmon of weight 85 N in 8.0 cm if the fish is initially drifting at 2.5 m/s? Assume a constant deceleration.

Two conducting wires each of length L are...

Two conducting wires each of length L are connected to a knob, whereby a total electric charge Q is deposited onto two small spherical metallic spheres, each of mass m and diameter d, at the end of the wires. We observe each wire of this electroscope to lie at an angle q from the vertical. Find an expression for the charge Q

Kinetic frictional force for a skier: Work done, magnitude of force

A 63 kg skier coasts up a snow-covered hill that makes an angle of 25 degrees with the horizontal. The initial speed of the skier is 6.6 m/s. After coasting a distance of 1.9 m up the slope, the speed of the skier is 4.4 m/s. (a) Find the work done by the kinetic frictional force that acts on the skis. (b) What is the magni

Power, work

A car can accelerate from rest to 25 m/sec in 12 seconds on a level road. The weight of the car is 10,000 newtons. Determine (a) power used in the acceleration in Kw. (b) Maximum speeed it will be able to maintain on an uphill road of angle 30 degrees. (c) Work done by the force during the first 5 seconds from start. (d) avera

Simple Harmonic Motion: Write a program to integrate an equation

See the attached file for the formulas. Determine an appropriate step size h by assuming that an h that works as expected for simple harmonic motion is good enough for the given initial angle. In particular, if the position at the end of one period is within 0.1% of the original point, we'll be satisfied.

Matrix representation

Find the unitary transformation which transforms into a diagonal matrix and verify that the diagonal elements are 0 , 3, and 3

Gravitational force

Mars has a mass of about 6.4 x 10^23 kg, and its moon Phobos has a mass of about 9.6 x 10^15 kg. If the magnitude of the gravitational force between the two bodies is 4.6 x 10^15 N, how far apart are Mars and Phobos? Please show the work, answer and the formulas you used. Thanks!

Work/kinetic friction on a system moving at constant speed.

"A 276 kg piano slides 4.02 m down a 30.2° incline and is kept from accelerating by a man who is pushing back on it parallel to the incline, as seen in the figure (attached in a Word file). The effective coefficient of kinetic friction is 0.400. Calculate the work done by the man on the piano." See attached file for full pro

Concepts clarification

Clarify: uniform Circular Motion Potential Energry Work Kinetic Energy Conservation of Engery Work by External Forces Newtons Laws 1,2,3 I need your help on what are the main things i would need to know from those areas in-order to solve relating problems