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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

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

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.

Matrix representation

Find the unitary transformation which transforms into a diagonal matrix and verify that the diagonal elements are 0 , 3, and 3

Gravitational force

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

Concepts clarification

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

Work and Energy: 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

Pulley problem

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

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

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 ?

X-ray production

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


A positive charge of 2X10-12 Coulombs placed 10cm from another charge experiences a repulsive force of 9X10-9 Newtons. What is the sign and magnitude of the other charge?

Thermal conductivity comparison

Which of the following cylindrical rods of the same material with its ends at the same steady difference of temperature will conduct maximum heat ? 1. Lenght 100 cm & radius 1 cm 2. length 200 cm & radius 1 cm 3. length 400 cm & radius 2 cm 4. length 100 cm & radius 2 cm

Lorry descending a hill: Force applied by the brakes

A lorry travelling on the level road at 40 km/h can be stopped by its brakes in a distance 16 m. Find the speed from which it can be brought to rest in the same distance when descending a hill whose angle of slope is Sin^-1 [1/15]

Sound waves: temperature dependence

(1) How will the pitch of an organ pipe be affected by change of temperature and humidity ? (2)Why do the sound waves travel through longer distances during night than during day ? (3)When a hot body cools a cool one, are their temperature changes equal in magnitude ?

Calculating the specific temperature that balls will sink in benzene.

Benzene has a density of 0.90gm/cm^3 at 0 deg C and a coefficient of cubical expansion of 0.0012 per deg Celsius. Wooden balls (of density 0.88g/cm^3) therefore float in it at 0 deg Celsius. If the wood has a mean coefficient of linear expansion of 4 x 10^-5 per deg Celsius, calculate at what temperature the balls will just sink

Springs: Different force constants.

Springs A and B are identical except that A is stiffer than B, that is the force constant Ka is greater than the force constant Kb. On which spring is more work expended if, (a) They are stretched by the same amount? (b) They are stretched by the same force?