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Breaking Load Problem

A fireman wants to slide down a rope. The breaking load for the rope is 3/4th of the weight of the man. With what minimum acceleration should the fireman slide down?

Force of Friction over a Pulley

1. Two masses are attached with a pulley over an incline which is over a platform. The top of the incline to the ground is 6m. There is one mass on that ramp which is 5.0kg. The other mass which is hanging freely off the ramp is 20.0kg. The force of kinetic friction between the 5.0kg mass and the ramp is .26. The 5.0kg mass is a

Bounce for a moving car

The car with its passengers is traveling along a horizontal road when it suddenly runs onto a new piece of road surface, raised 5.5 cm above the old surface. Assume that this suddenly raises the wheels and the bottom ends of the springs through 5.5 cm before the body of the car begins to move upward. In the ensuing rebound, are

Work Done at Angle

An object of mass = 2 kg is pulled by a constant force F = 4 N for a horizontal distance of 2 m. (the rope pulling the mass is at an angle of 30 degrees above the horizontal) What is the work done along the positive x axis? Neglect friction. 8 kg m/s^2 8 kg m^2/s^2 7 kg m/s^2 7 kg m^2/s^2

Plane Reversing Course

1. In airplane traveling at 529 km/hr needs to reverse its course. The pilot decides to accomplish this by banking the wings at an angle of 41.0 degrees. a) Find the time needed to reverse course. b) How heavy would a 56 kg passenger feel during the turn? In other words, what would be the magnitude of the total force exerte

Projectile motion with angles

A football is kicked at an angle of 50 degrees and travels a distance of 20 m before hitting the ground. a. What is the initial speed of the ball? b. How long is it in flight? c. How high does it rise?

Resulting acceleration

A 3.00-kg mass and a 5.00-kg mass hang vertically at the ends of a rope that goes over an ideal pulley. If the masses are released, what is the resulting acceleration of the masses? 0 m/ 3.68 m/ 2.45 m/ 6.13 m/

Calculate the mass of a car in acceleration

To determine the mass of a car, a student (with a friend at the wheel) pushes the car holding a bathroom scale between himself and the car and carefully maintains a constant reading of 400 N on the scale while the car accelerates on level ground. At the conclusion of the experiment his friend reports that the car accelerated fro

Two objects forces

You apply the same force to two objects. Object 1 has mass M and object 2 has mass 5M. The acceleration of object 2 is Choices: five times that of object 1. the same as that of object 1. one-fifth as that of object 1. has no relation to that of object 1.

Vector questions

1. The vector expression of an acceleration can be obtained by: a. Differentiation position vector once b. Differentiation velocity vector once c. Differentiation position vector three times d. Differentiation velocity vector twice 2. The work of forces acting on a rigid body can be expressed as: a. the dot product

Find the average acceleration

The positions of two blocks at successive 0.20 second time intervals are represented by numbered squares in the diagram below. The blocks are moving toward the right. 20. Do the blocks ever have the same speed? Explain the reasoning behind your answer. A. No B. Yes at instant 2 C. Yes at instant 5 D. Yes at insta

Classical Kinematics and Cyclist Speeds

Two cyclists are racing on a track that looks like the following diagram (see attachment). Each horizontal section is 100 metres long. Cyclist 1: Angelo has a mass that is twice of Cyclist 2: Jackie. Both Angelo and Jackie start at rest and apply an equal Force to their bikes in section A, after which each of them stops ped

Gas dynamics problem.

Helium gas enters an adiabatic nozzle steadily at 500 degrees C and 600 kPa with a low velocity, and exits at a pressure of 90 kPa. What is the highest possible velocity of helium gas at the nozzle exit?

Acceleration, Velocity & Net Force on a Car

A 1500-kg car travels at a constant speed of 22m/s around a circular track that has a radius of 85m. Determine the: A. Magnitude of Acceleration of the car B. Average Velocity of the car during one revolution C. Magnitude of the net force that acts on the car

Set of three problems on Newton's laws of motion

1) A window washer of mass M is sitting on a platform suspended by a system of cables and pulleys as shown (see attachment). He is pulling on the cable with a force of magnitude F . The cables and pulleys are ideal (massless and frictionless), and the platform has negligible mass. Find the magnitude of the minimum force that a

Rotational Kinematics of a Rotor

The angular speed of the rotor in a centrifuge increases from 420 to 1420 rad/s in a time of 5.00 s. (a.)What is the angle through which the rotor turns. (b.)What is the magnitude of the angular acceleration?

Physics Questions

(26) A 6.0 kg object is brought to the Moon, where the acceleration due to gravity is only one sixth of that on the Earth. a) The mass of the object on the Moon is (1) zero, (2) 1.0 kg, (3) 6.0 kg or (4) 36kg. Why? b) What is the weight of the object on the Moon? (41) The mass of the object is 10kg and the force on the object

Car acceleration problem

1,000kg car is parked on hill. The car rolls down hill accelerating 10mph, and hits a guard rail pushes it back 1.5 meters What acceleration did the car experience and how much force must the guard rail have supplied to slow it down.

Calculations for Velocity

A spacecraft is traveling with a velocity of vox=5480 m/s along the x direction. Two engines are turned on for a time of 842s. One engine gives the spacecraft an acceleration in the x direction of ax = 1.20 m/s^2, while the other gives it an acceleration in the y direction of ay=8.40 m/s^2. At the end of the firing what is a) vx

There is a clever kitchen gadet for drying lettuce leaves after you

There is a clever kitchen gadet for drying lettuce leaves after you wash them.It consists of of cylindrical container mounted so that it can be rotated about its axis by turning a hnd crank. The outer wall of the cylinder is perforated with small holes. you put the wet leaves in the container and turn the cranks to spin off the

What is the magnitude of the motorcycle's acceleration?

A 292 kg motorcycle is accelerating up along a ramp that is inclined 30 degrees above the horizontal. The propulsion force pushing the motorcycle up the ramp is 3150 N and air resistance produces a force of 250 N that opposes the motion. What is the magnitude of the motorcycle's acceleration?

Satellites and Circular Orbit

Communication satellites are placed in a circular orbit that is 3.59 x 10^7 m above the surface of the earth. What is the magnitude of the acceleration due to gravity at this distance?

Understanding Acceleration

A 50.0g superball traveling at 25.0 m/s bounces off a brick wall and rebounds at 22.0m/s. A high-speed camera records this event. If the ball is in contact with the wall for 3.50ms, what is the magnitude of the average acceleration of the ball during this time interval? (note 1 ms= 10^-3 s.) Textbook answer to this problem is