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Classical Mechanics

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 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

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

Pulley

What is a pulley? where is it used?

Force and Shear Moduli

Two metal plates are held together by two steel rivets, each of diameter 0.20 cm and length 1.0 cm. How much force must be applied parallel to the plates to shear off both rivets? The shear modulus of steel is 8.2 x 10^10.

Solving an Elasticity Problem

A phone line 2.0 m in diameter and 0.5 km long is stretched 0.5 m by a force of 4000 N. Determine: 1. the stress on the wire 2. the strain on the wire 3.Young's modulus for the cable material.

Speed of a Rolling Hoop

A hoop of radius 0.5 m and a mass of 0.2kg is released from rest and allowed to roll down an inclined plane. How fast is it moving after being dropped from a vertical distance of 3m? a. 5.4 m/s b. 3.8 m/s c. 7.7 m/s d. 2.2 m/s

Linear Momentum and Collisions

A 16 g rifle bullet traveling 150 m/s buries itself in a 4.0 kg pendulum hanging on a 3.3 m long string, which makes the pendulum swing upward in an arc. Determine the horizontal component of the pendulum's displacement.

Physics: Springs and Compression

1. A spring is compressed 10 cm by pushing a body against it. When released the spring pushes the body towards another identical spring. The body must slide over a rough floor in order to reach the second spring. When it makes contact the body compresses the opposite spring by 8 cm. Once again the body is forced back over the ro

Finding the Center of Mass of a Rod

A 3.0 kg rod of length 5.0 m has at opposite ends point masses of 4.0 kg and 6.0 kg(a) Will the center of mass of this system be (1) nearer to the 4.0 kg mass, (2) nearer to the 6.0 kg mass, or (3) at the center of the rod? Why? (b) Where is the center of mass of the system?

Springs

Question: When an object weighing 50 N is hung from a vertical spring, it stretches 20 cm. Calculate the spring's elastic constant. If the 50 N load were replaced with a 80 N weight, how far would the spring stretch?

Falling Objects

A first stone is dropped from the roof of a building. 2.50 s after that, a second stone is thrown straight down with an initial speed of 30.0 m/s, and it is observed that the two stones land at the same time. (a) How long did it take the first stone to reach the ground? (b) How high is the building? (c) What are the spe

Kinematics in One Dimension

An automobile traveling v = 85 km/h overtakes a L = 1.15 km long train traveling in the same direction on a track parallel to the road. If the train's speed is 80 km/h, how long does it take the car to pass it (min), and how far will the car have traveled in this time? (km) What are the results if the car and train are travel

Tension on a bridge cable

A knight in armour on a horse leaves the castle. His squire has mistakenly lowered the drawbridge 20 degrees below the horizontal. The knight and his horse stop when their combined center of mass are 1 metre from the end of the bridge. The uniform bridge is 8 metres long and has a mass of 2000 kg. The lift cable is attached t

Damped Egg on a Spring

Please do not place your response in a .pdf or .cdx format, but Word documents are okay. Thanks! Here's the actual problem: A 50.0-g hard-boiled egg moves on the end of a spring with force constant k=25.0 N/m. It is released with an amplitude 0.300 m. A damping force F_x=-bv acts on the egg. After it oscillates for 5.00 s,

Analyzing Simple Harmonic Motion

The applet at the following site (http://mp.pearsoncmg.com/probhtml/ActivePhysics/pt1a/Media/Vibrations/PositionGraphsEqns/Sim4.html) shows two masses on springs, each accompanied by a graph of its position versus time. A) What is an expression for x_1 (t), the position of mass I as a function of time? Assume that position i

Speed of Bullet

A 5.00-g bullet is shot through a 1.00-kg wood block suspended on a string 2.000 m long. The center of mass of the block rises a distance of 0.45 cm.Find the speed of the bullet as it emerges from the block if its initial speed is 450 m/s.

Maximum Angle of Incline

A spherical shell starts from rest and rolls down an incline. The coefficient of static friction between the shell and incline is (Us=.2). What is the maximum angle of incline such that the shell will roll without slippage?

Sliding Plates

Each of the three plates has a mass of 10kg. If the coefficients of static and kinetic friction at each surface of contact are us = 0.3 and uk = 0.2 respectively, determine the acceleration of each plate when the three horizontal forces are applied. See attachment for diagram.

Classical mechanics problems - vectors operations and uniform acceleration

13. A bus travels at an average speed of 90 km/h. On average, how far does the bus travel in 20 min? Is this distance the magnitude of the actual displacement of the bus? Explain. 17. A student runs 30 m east, 40 m north, and 50 m west. (a) The magnitude of the student's net displacement is (1) between 0 and 20 m, (2) bet

Projectile motion

A missile is launched at a speed of 25 m/s at an angle of to 35the ground. What is its range? How high did it go vertically? Answer without using calculus.

Finding the Center of Mass of a Nonlinear Thin Rod

A thin non-uniform rod is 4 meters in length and has a linear density D, (mass per unit length), in kg/m, which is expressed by D= 3 + 5 x in which x is the distance in meters from the zero end of the rod. Find the x coordinate of the center of mass of the rod.