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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?

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.

tension in the rope and acceleration

Blocks A, B & C are connected by ropes of negligible mass. Both A & B weigh 25.0 N each, and the coefficient of kinetic friction between each box block and the surface is 0.35. Block C descends with constant velocity. a) Find tension in the rope connecting blocks A & B. b) What is the weight of block C? c) If rope connect

One along a straight line and the other along a curved path.

One of the toughest problem in Dynamics. Problem- At the instant shown, car A has a speed of 20 km/h, which is being increased at the rate of 300 km/h2 as the car enters an expressway. At the same instant, car B is decelerating at 250 km/h2 while traveling forward at 100 km/h. Determine the velocity and acceleration of A

Acceleration of skateboarder rolling down a ramp

A skateboarder, starting from rest, rolls down a 12.0 m ramp. When she arrives at the bottom of the ramp her speed is 7.70 m/s. a.) what is the magnitude of her acceleration? b.) if the ramp is inclined at 25.0 degrees with respect to the ground, what is the component of her acceleration that is parallel to the ground?

How many rotations a blood sample makes in a centrifuge

A centrifuge is a device in which a small container of material is rotated at a high speed on a circular path. Such a device is used in medical laboratories, for instance, to cause the more dense red blood cells to settle through the less dense blood serum and collect at the bottom of the container. Suppose the centripetal accel

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?

Kinetic Frictional Force on the Box in the Elevator

A 6.00 kg box is sliding across the horizontal floor of an elevator. The coefficient of kinetic friction between the box and the floor is .360. What is the kinetic frictional force that acts on the box when the elevator is a.)stationary, b.) accelerating upward with an acceleration whose magnitude is 1.20 m/s^2 and c.) accelera

acceleration of a superball

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

Motion on a Sphere Particles

Motion on a sphere. A particle of mass m is constrained to move on the surface of a sphere of radius R by an applied force F (a vector) and a function of Theta, Phi. Write the equation of motion.

Jet Fighter Circular Acceleration in Vertical Plane

A jet fighter can withstand a max acceleration of 9g's; The plane is pointed vertically downward at Mach 3 and will be pulled from the dive in a circular manuver (befoe crashing). a. Where does max acceleration occur ? b. What is the minimum radius the pilot can take? Please show all details.

Find the Components of the Acceleration Vector

A (acceleration) is an acceleration vector, find the components of this vector in spherical coordinates; please show all work, in detail, Not: a is a general vector in spherical cootdinates. the components can be expressed in terms of Theta, Phi and R

Motion Diagram Description

(See attached file for full problem description with diagrams) 1. If an object is moving at a constant velocity, then we can assert that: a. there must be a force in the direction of the velocity b. there must be no force in the direction of the velocity c. there must be no net force Justify your answer! 2. To tight

A Simple Harmonic Oscillator

A 10-g particle is undergoing simple harmonic motion with an amplitude of 2.0 x 10^-3 m and a maximum acceleration of magnitude 8.0 x 10^-3 m/s^2. The phase angle is -pi/3 rad. a) Write and equation for the force on the particle as a function of time. b) What is the period of the motion? c) What is the maximum speed of the p

Motion along a straight line and free falling objects

This problem set contains 15 multiple choice questions on motion along a straight line. First three questions are typed below. 50. A stone is released from a balloon that is descending at a constant speed of 10 m/s. Neglecting air resistance, after 20 s the speed of the stone is: 51. An object dropped from the window of

Motion Equations Required

Answers are given in attachment, but please set up each problem with the math equations needed and show step by step how to do each problems that involves math to get the answer given. Skip any problems that ask those questions that you have to pick a sentence answer. (See attached file for full problem description) 6. A

What is the mass ratio of the boxes?

Two boxes are seen to accelerate at the same rate when a force F is applied to the first box and 4F is applied to the second box. What is the mass ratio of the boxes?

Motion on a circular path. (horizontal and vertical)

1. The tub of a washer goes into its spin-dry cycle, starting from rest and reaching an angular speed of 3.0 rev/s in 7.0 s. At this point the person doing the laundry opens the lid, and a safety switch turns off the washer. The tub slows to rest in 10.0 s. Through how many revolutions does the tub turn during this 17 s interval

Problem Set

(See attached file for full problem description) --- 2. The leg and cast in Figure P4.18 weigh 270 N, with the center of mass as indicated by the blue arrow in the diagram. The counterbalance w1 weighs 135 N. Determine the weight w2 and the angle needed so that no force is exerted on the hip joint by the leg plus cast.

Rotational Dynamics/angular acceleration using a turntable for the experiment

The claim that the acceleration of the falling mass is the same as the tangential acceleration of a point at the lever arm distance from the axis is : a = (r)(alpha), where a is the acceleration of the falling mass, r is the lever arm distance, and alpha is the angular acceleration of the turntable. Why is this claim valid? Use