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Strength of a fishing line

1. The tension at which a fishing line snaps is commonly called the line's "strength." What minimum strength is needed for a line that is to stop a salmon of weight 85 N in 8.0 cm if the fish is initially drifting at 2.5 m/s? Assume a constant deceleration.

Point Charges

Two point charges each of magnitude 2.00 ìC are located on the x axis. One is at x = 1.00 m, and the other is at x = -1.00 m. (a) Determine the electric potential on the y axis at y = 0.500 m. (b) Calculate the change in electric potential energy of the system as a third charge of -3.00 ìC is brought from infinitely far

Throwing a stone off a bridge

A man standing on a bridge 30m above the water throws a stone in a horizontal direction. Knowing that the stone hits the water 40m from a point on the water directly below the man determine (a)the initial velocity of the stone (b)the distance at which the stone would hit the water if it were thrown with the same velocity from a

Two conducting wires each of length L are...

Two conducting wires each of length L are connected to a knob, whereby a total electric charge Q is deposited onto two small spherical metallic spheres, each of mass m and diameter d, at the end of the wires. We observe each wire of this electroscope to lie at an angle q from the vertical. Find an expression for the charge Q

Kinetic frictional force for a skier: Work done, magnitude of force

A 63 kg skier coasts up a snow-covered hill that makes an angle of 25 degrees with the horizontal. The initial speed of the skier is 6.6 m/s. After coasting a distance of 1.9 m up the slope, the speed of the skier is 4.4 m/s. (a) Find the work done by the kinetic frictional force that acts on the skis. (b) What is the magni

Energy Theorem and Kinetic Energy

A fighter jet is launched from an aircraft carrier with the aid of its own engines and a steam-powered catapult. The thrust of its engines is 2.3 x 10^5 N. In being launched from rest it moves through a distance of 87 m and has a kinetic energy of 4.5 x 10^7 J at lift-off. What is the work done on the jet by the catapult?

Work Done By Constant Force: gravitational force; escalator force

A 75.0 kg man is riding an escalator in a shopping mall. The escalator moves the man at a constant velocity from ground level to the floor above, a vertical height of 4.60 m. What is the work done on the man by (a)the gravitational force and (B) the escalator?

Power, work

A car can accelerate from rest to 25 m/sec in 12 seconds on a level road. The weight of the car is 10,000 newtons. Determine (a) power used in the acceleration in Kw. (b) Maximum speeed it will be able to maintain on an uphill road of angle 30 degrees. (c) Work done by the force during the first 5 seconds from start. (d) avera

Working with a compressed spring - mass attached to spring

A 5kg block free to move on a horizontal surface is attached to a spring. The spring is compressed 0.1m from equilibrium and then released. The speed of the block is 1.2m/s at the unstressed equilibrium position of the spring. The same experiment is now repeated on a surface with a coefficent of kinetic friction = 0.3. A.

Working with a Current Carrying Wire in Magnetic Field

A long straight wire having a mass of 0.025 kg/m is suspended by threads. When the wire carries a 20-A current, it experiences a horizontal magnetic force that deflects it to an equilibrium angle of 10 degrees. What are the magnitude and direction of the magnetic field? (Assume that field vectors are perpendicular to the wire)

Work/kinetic friction on a system moving at constant speed.

"A 276 kg piano slides 4.02 m down a 30.2° incline and is kept from accelerating by a man who is pushing back on it parallel to the incline, as seen in the figure (attached in a Word file). The effective coefficient of kinetic friction is 0.400. Calculate the work done by the man on the piano." See attached file for full pro

Potential energy and conservative forces: Determining distance

1. A 1.9-kg block slides down a frictionless ramp. The top of the ramp is 1.5 m above the ground; the bottom of the ramp is 0.25 m above the ground. The block leaves the ramp moving horizontally, and lands a horizontal distance d away. Find the distance d. 2. Suppose the ramp is not frictionless. Find the distance d for the c

Vectors

Vector A is 3.00 units in length and points along the positive x-axis. Vector B is 4.00 units in length and points along the negative y-axis. Use the graphical methods to find the magnitude and direction of the following vector: B.) A+B The work I need to show to complete this problem is a free body diagram, formulas, work

X-ray production

X-ray production: dependence of wavelength and intensity on various parameters. Tips to remember.

Elastic collision: Finding the unknown mass

A body of 2kg mass makes an elastic collision with another body at rest and afterwards, continues to move in the original direction but with one fourth of its original speed. What is the mass of the struck body?

Calculate the Force of a Spring Function

On a frictionless table, one end of a spring is fixed. A cord attached to the free end pulls it along a meter scale beginning from 0. A record is made of the position of the free end, x, and the resisting force, F, exerted by the spring on the cord. SEE ATTACHMENT #1 for the parameters and a record of F vs x, showing position

Archimedes Principle: An object, part aluminum, part wood

See attached file. Two blocks are cemented together top to bottom and the whole object is placed in water. Known values are the density of the wood Dw= .650 kg/m^3, of aluminum Da = 2700 kg/m^3, and of water Dliq= 1000 kg/m^3. See attachment #1 for diagram, (not to scale). PART a. If the object barely floats, with the top

Pressure, Height, and Kelvins in a Gas-Filled Cylinder

A frictionless gas-filled cylinder is fitted with a movable piston. The block resting on the top of the piston determines the constant pressure that the gas has. The height h is 0.120 m when the temperature is 273K and increases as the temperature increases. What is the value of h when the temperature reaches 318K?

Working with Youngs Modulus

Copper has a breaking stress of 3 x 10^8 N/m2. (a) What is the maximum load that can be hung from a copper wire of diameter of 0.42 mm before it breaks? (b) If half this maximum load is hung from the wire, by what percentage of its length will it stretch?

Working with static equilibrium

A ladder rests against a frictionless vertical wall. The coefficient of static friction between the ladder and the floor is 0.44. What is the smallest angle at which the ladder will remain stationary?

Working with stress, strain and Hooke's Law.

An 1800 kg car, being lifted at a steady speed by a crane, hangs at the end of a cable whose radius is 6.0 * 10^-3 m. The cable is 15m in length and stretches by 8.0 *10^-3 m because of the weight of the car. Find: (a) the stress (b) the strain (c) Young's modulus for the cable

Working with elastic potential energy and a bowstring.

An archer pulls the bowstring back for a distance of 0.470 m before releasing the arrow. The bow and string act like a spring whose spring constant is 425 N/m. (a) What is the elastic potential energy of the drawn bow? (b) The arrow has a mass of 0.0300 kg. How fast is it traveling when it leaves the bow?

Moment of Inertia of a thin uniform rod by integration

A thin, uniform rod has length L and mass M. a. Find by integration its moment of inertia about an axis perpendicular to the rod at one end. b. Find by integration its moment of inertia about an axis perpencicular to the rod at its center of mass.