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Stress in the Bones of the Arm during the Swing

1. Find an equation for the terminal velocity of a sphere falling through a viscous fluid (like water or blood). How does the terminal velocity scale with the size of the falling object? Assume that the density of that object is much larger than that of the fluid through which it falls (neglect buoyancy). a. V ~ L^-3 b. V ~

Physics Questions: Force, Work and Energy

Physical science (8th edition) by Bill W. Tillery Parallel Exercises 1. How much work is done when a force of 800.0 Ni s exerted while pushing a crate across a level floor for a distance of 1.5m? 2. A force of 400.0 N is exerted on a 1,250 N car while moving it a distance of 3.0 m. How much work was done on the car?


1. A 4.5 kg block is at rest on a table when it is attached to a second mass, m2 hanging over a pulley. The static coefficient of friction between the block and the table is 0.56 and kinetic coefficient is 0.42, respectively. The hanging mass, m2 is chosen to be 2.4 kg. a) Will this choice for m2 set the system in motion? b)

Physics: Velocity, Magnitude and Direction

Hi, I need some assistance with the following questions: 1. A cannon ball is fired with a velocity of 48 m/s at 42 degrees up from the horizontal. Assume that it lands at the same level as it was fired from. a. Find the maximum height of the cannon ball. b. Find the total time the cannon ball is in the air. c. Find the

9 Physics Problems and Solutions

1. To qualify for the finals of a racing event, a race car must achieve an average speed of 220 km/h on a track with a total length of 2400 m. If a particular car covers the first 1000 m of the track with an average speed of 180 km/h, what minimum average speed must it have on the remainder of the track to qualify? 3. How lon

Frictional Force and Velocity of Water

A 150-lb fireman is holding a hose which has a nozzle diameter of 1 inch and hose diameter of 2 inches. If the velocity of the water at discharge is 60 ft/s - determine the resultant normal and frictional force acting on the man's feet at the ground. (Neglect the weight of the hose and the water within it. yw = 62.4 lb/ft3).

7 problems on rotational motion and two problems on density

1. Competitive divers pull their limbs in a curl up their bodies when they do flips. Just before entering the water, they fully extend their limbs to enter straight down. Explain the effect of both actions on their angular velocity. What is the effect of these actions on their angular momentum? 2. (A) Show that for a hoop of

Derivatives : Displacement, Velocity and Acceleration

A car brakes in an emergency, the moment the brakes are first applied is t=0. the car's distance, s, from the point at which the brakes were first applied is given by: S = -0.1t^3 + 20t + 0.1 (i) Differentiate s to find formulae for the velocity and acceleration. (ii) Find the time at which the car comes to a stop. (iii)

Force on Current Carrying Wires and Drift Velocity

Please see the attached file for the problem statement, and provide a fully worked-out solution. In order to get an idea of the magnitude of magnetic forces, find the force per unit length between very long equal and opposite 10 ampere currents separated by 1 centimeter. Find the ratio of this to the weight per unit length of

Electron drift velocity

Calculate the drift velocity of electrons in a copper wire given the current flowing in it, its diameter and density. A copper wire 2.5 millimeters in diameter is carrying a current of 10 amperes. Assume one free electron per copper atom and find the magnitude of the drift velocity. [Copper has a density of 8.92 grams/(cent

Absolute and Gauge Pressure

A dam to create a large fresh water lake is constructed. It will be approximately 14 meters deep. A horizontal pipe 1.2 meters long and 4 cm in diameter will pass through the dam at a depth of 7 meters to allow for release of the water in emergencies and for sampling. In normal situations, a plug will secure the pipe opening.

Ideal Ball Projectile Motion

A ball is thrown directly downward, with an initial speed of 8.50 m/s, from a height of 31.0 m. After what time interval does the ball strike the ground?

Toy Cars: Velocity, position, and acceleration

At t = 0, one toy car is set rolling on a straight track with initial position 13.0 cm, initial velocity -3.5 cm/s, and constant acceleration 2.50 cm/(s^2). At the same moment, another toy car is set rolling on an adjacent track with initial position 10.5 cm, an initial velocity of 6.10 cm/s, and constant zero acceleration. (a)

4 Problems: Vectors, Displacement and equations of motion.

Please see the attached file for full problem description. 1.) A basketball player runs down the court, following the path indicated by the vectors A, B, and C in Figure 3-38. The magnitudes of these three vectors are: A = 10.0 m, B = 21.0 m, and C = 7.0 m. Let the +x axis point to the right and the +y axis point to the far s

Physics - Pressure and Volume

1. Calculate the following. a. 100 ml of liquid A has a mass of 250 g. What is its density, in kg/L? (Note: 1 L = 1000 ml = 0.001 m3) b. Liquid B has a specific gravity of 0.98. How much does 1 L weigh, in an Earth-standard gravitational field? 2. The pipe shown above expands from an internal diameter of 3 cm to an

velocity and acceleration..

4.) A car has an average speed of 80.0 km/h for one hour, then an average speed of 90.0 km/h for two hours during a three-hour trip What was the average speed for the three-hour trip? 5.) What is the acceleration of a car that moves from a speed of 5.0 m/s to a speed of 15m/s during a time of 6.0 s? 10.) An archer shoots a

Displacement vs Time and Velocity vs Time

Hi, I need assistance on this one problem. I need all work shown to understand. The distance between windowsills I am confused about. See attachment for diagram: Please apply the techniques used in Lab 3 (particularly the ticker tape) to the following photo: Distance between windowsills is 3.15 meters. Three photographs

Magnetic Force and Magnetic Fields

A uniform magnetic field of magnitude B=1.2 teslas is directed toward the bottom of the page in the -y direction. At time t=0, a proton p in the field is moving in the plane of the page with a speed v=4 x 10^7 meters per second in a direction 30 degrees above the +x axis. a.) Calculate the magnetic force on the proton at t=0

Torricelli's Theorem

Water stands at a depth H in a large open tank whose side walls are vertical (see attachment for figure). A hole is made in one of the walls at a depth h below the water surface. a) At what distance R from the foot of the wall does the emerging stream strike the floor? Express your answer in terms of the given quantities.

momentum and impulse

Please see attachment. Thank You your help is greatly needed. 1. A stunt person jumps from the roof of a tall building, but no injury occurs because the person lands on a large, air-filled bag. Which one of the following best describes why no injury occurs? 2. Jennifer is walking at 1.63 m/s. If Jennifer weighs 583 N, what

Birefringent Materials Optic Axis

What is meant by the optic axis of a uniaxial birefringent crystal? Could you please describe and explain how birefringent materials may be used to produce linearly and circularly polarized light from unpolarized light? Thank you.

Projectile motion

Please see the attached file. 1. A rocket is launched at an angle of 53.0° above the horizontal with an initial speed of 100 m/s. The rocket moves for 3.00 s along its initial line of motion with an acceleration of 30.0 m/s2. At this time, its engines fail and the rocket proceeds to move as a projectile. Find (a) the max

Flywheel Kinematics

A heavy flywheel is accelerated (rotationally) by a motor that provides constant torque and therefore a constant angular acceleration alpha. The flywheel is assumed to be stationary at time t = 0 in Parts A, B, and C of this problem. a). Find the time t_10 it takes to accelerate the flywheel to 10.0 rps (revolutions per secon

Spring and Projectile of a thrown ball

A child's toy consists of a block that attaches to a table with a suction cup, a spring connected to that block, a ball, and a launching ramp. The spring has a spring constant, k, the ball has a mass, m , and the ramp rises a height, y, above the surface of the table, the surface of which is a height, H, above the ground. Initia

Angular Displacement and Motion

1. The angular displacement of a human centrifuge, of length 30 ft, is given by (theta)= 4[t + 30*e^(-.03t)-30]radians where t is in seconds and and t=0 is start up. If the passenger loses consciousness at an acceleration of 10g's determine the time this would occur. Verify the tangential acceleration is small compared to

velocity, acceleration, distance motion

Hello I need help with the following Physics problems. 9. A train approaches a small town with a constant velocity of +28.6 m/s. The operator applies the brake, reducing the train's velocity to +11.4 m/s. If the average acceleration of the train during brake is -1.35 m/s^2. For what elapsed time does the operator apply the br

Determining Magnitude of Velocity and Acceleration

See the attached file for diagram. The fixed horizontal guide carries a pin P whose motion is controlled by the rotating slotted arm OA. If the arm is revolving about O at the constant rate of 2 radians/sec (angular velocity)for the for the interval allowed by the horizontal guide determine the magnitudes of the velocity an