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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

Height of an IV Fluid Bag Suspended

I need a mathematical explanation of part a in question 25 of the attached jpeg file. Find the height at which the bag of fluid must be suspended above the patient for the IV to work properly

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.

Simple Harmonic Motion: Write a program to integrate an equation

See the attached file for the formulas. Determine an appropriate step size h by assuming that an h that works as expected for simple harmonic motion is good enough for the given initial angle. In particular, if the position at the end of one period is within 0.1% of the original point, we'll be satisfied.

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)

Working with Newton's law of gravitation

Mars has a mass of about 6.4 x 10^23 kg, and its moon Phobos has a mass of about 9.6 x 10^15 kg. If the magnitude of the gravitational force between the two bodies is 4.6 x 10^15 N, how far apart are Mars and Phobos? Please show the work, answer and the formulas you used. Thanks!

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

Stone is released from rest at top of a vertical cliff

Q1. A stone of mass 80 grams is released from rest at the top of a vertical cliff. After falling for 3 seconds, it reaches the ground and penetrates 9 cm into the ground. Calculate: 1. the height of the cliff 2. the average force resisting the penetration (assume gravitational acceleration g=10m/sec2)

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

Description of Work, energy and motion

Clarify: uniform Circular Motion Potential Energry Work Kinetic Energy Conservation of Engery Work by External Forces Newtons Laws 1,2,3 I need your help on what are the main things i would need to know from those areas in-order to solve relating problems

Speed of block, maximum compression of spring, block rebounds

On an incline a 2.00 kg block is released 4.00m from a long spring with a force constant k= 60.0 N/m that is attached at the bottom of the incline. The incline makes the angle of 53 degrees with the horizontal, and the coefficients of friction between the block and the incline are u static = .40 and uk= .20. a) what is the s

Work done by a constant force: Lifting and carrying a pumpkin from a field

I think I have both answers, but I really need (b) explained. You go to a pumpkin patch to select your Halloween pumpkin. You lift the 3.2kg pumpkin to a height of 1.2 m, then carry it 50.0 m on level ground to the checkout stand. (a) Calculate the work you do on the pumpkin as you lift it from the ground, and (b) How m

Working with pulleys - rope sliding down a pulley

A thick rope with a length of 5m is draped over a pulley, such that the right side y=3m is dangling free and on the left side L-y=2m is dangling free. The rope has a mass of 10kg. Since the longer side is more massive than the shorter side, the rope begins falling downward, with the shorter end going up towards the pulley. As

By integration, find the work done between given limits.

See attached file. A perfectly elastic rubber framework is stretched by a force applied to its end. This force as a function of the x coordinate of the end is: (1) F = 52.8 x + 38.4 x^2 PART a. By integration, find the work done by this applied force from position x1=.5 m to x2= 1 m. PART b. With the end at position

Use graphical methods to find the magnitude and direction of the vector: B.) A-B

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


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

Working with a Rolling Sphere on Incline

As shown in the figure a uniform solid sphere rolls on a horizontal surface at 30 m/s and then rolls up the incline. If frictional losses are negligible, what will be the value of its height when the it stops ?