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Magnitude of force and acceleration

A 4.44 kg block located on a horizontal frictionless floor is pulled by a cord that exerts a force F=10.7N at an angle theta=22.0degrees above the horizontal, as shown. What is the magnitude of the acceleration of the block when the force is applied? What is the magnitude of the normal force acting on the block when the force

Average Net Force/Acceleration

1. During a circus performance, a 73.0-kg human cannonball is shot out of an 17.7-m-long cannon. If the human cannonball spends 0.812 s in the cannon, determine the average net force exerted on him in the barrel of the cannon. (Assume an the acceleration is constant.) 2. A newly discovered planet has a mass that is 1.45 times

Electric Force and Coulomb's Law between Two Point Charges

Objects A and B are both positively charged. Both have a mass of 500 g, but A has twice the charge of B. When A and B are placed 50.0 cm apart, B experiences an electric force of 0.810 N. 1) How large is the force on A? 2) What are the charges q_A and q_B? 3) If the objects are released, what is the initial acceleration of

Acceleration and Force/Newton's Laws of Motion

Acceleration & Force : 1. Calculate the average acceleration of a car that changes speed from 0 m/s to 15 m/s in 5 s. 2. Suggest why placing wheels under a heavy box reduces the necessary force required to push it along at a constant speed. 3. Evaluate the change of motion in the following cases in which the forces o

Physics Questions on Impact, Speed, Acceleration

1. In her Mustang, Kelly rounds a curve onto a straight section of country road while traveling at 45 mph, only to find a fully loaded manure spreader completely blocking the road 37 m ahead of her. Startled, she travels at a constant velocity for 0.80 s of reaction time, then hits the brakes and slows with a constant accelerati

Elementary Differential Equations

64. (The clepsydra, or water clock) A 12 hour water clock is to be designed with the dimensions shaped like the surface obtained by revolving the curve y = f(x) around the y-axis. What should be this curve, and what should be the radius of the circular bottom hole, in order that the water level will fall at the constant rate o

Determine if the disk slips at this instant.

Problem # 9 - The semicircular disk having a mass of 10 kg is rotating at  = 4 rad/s at the instant  = 60 . If the coefficient of static friction at A is  s = 0.5, determine if the disk slips at this instant. See attached file for full problem description.

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

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/

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.

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?

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

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.

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?