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Newton's Second Law

Newton's Laws of Motion for an Athlete

An athlete whose mass is m is performing weight-lifting exercises. Starting from the rest position, he lifts, with constant acceleration, a barbell that weighs w. He lifts the barbell a distance of x in a time of t. Use Newton's laws to find the total force that his feet exert on the ground as he lifts the barbell. Take free

Pendulum tension calculation in horizontal string

A simple pendulum consists of a bob of mass 1.8 kg attached to a string of length 2.3 m. The pendulum is held at an angle of 30 Degrees from the vertical by a light horizontal string attached to a wall, as shown above. 1. Calculate the tension in the horizontal string. 2. The horizontal string is now cut close to the bob,

AP Physics 8-8

Please provide detailed steps. 8.8. Force of a Baseball Swing. A baseball has a mass of 0.145 Kg. a) If the velocity of a pitched ball has a magnitude of 45.0 m/s and the batted ball's velocity is 55.0 m/s in the opposite direction, find the magnitude of the change in momentum of the ball and of the impulse applied to it

Centripetal Force

A roller coaster at an amusement park has a dip that bottoms out in a vertical circle of radius r. A passenger feels the seat of the car pushing upward on her with a force equal to 2.3 times her weight as she goes through the dip. If r = 29.0 m, how fast is the roller coaster traveling at the bottom of the dip?

Pulley Problem

If an object with a mass of X kg sits on a frictionless table and another object with a mass of Y kg is connected to it by a wire over a frictionless pulley, how do you calculate the acceleration of the system and how do you calculate the tension of the wire?

Waves, Heat and Light and Oscillation

A damped harmonic oscillator consists of a mass M - 0.4 kg, attached to a spring with spring constant k - 0.20 N/m, all immersed in a viscous fluid that exerts a damping force F = -bv. The amplitude of the oscillation is observed to decrease by a factor of 2 after 10 oscillatory cycles. What is the value of b?

Skier on Slope Ignoring Friction

A skier traveling at 31.3 m/s encounters a 25.9 degree slope. If you could ignore friction, to the nearest meter, how far up the hill does he go? 114 meters But...If the coefficient of kinetic friction in the previous problem was actually 0.07 and the slope 30 degrees, to the nearest meter how far up the hill does he go?

Applying of Newton's Law

Three ropes are pulling on a blue ring. If F1=104 newtons and F2=134 to the nearest tenth of a newton what must F3 equal if the ring is not to move? See the attached file.

Applications of Newton's Law

The 65 kg man in the roller coaster car is sitting on a bathroom scale. If he is traveling at 40.4 m/s at the point shown and the radius of the vertical coaster track is 62 meters to the nearest newton, what does the scale read? What would be the answer if the roller coaster was at the bottom of the track? (See attached fi

Newton Laws of Motion - Traveling Plane

A plane traveling at 18.5 m/s is brought to rest in a distance of 135 meters. To the nearest hundredth of a m/s2 what is the magnitude of its acceleration? If the mass of the plane in the previous problem is 1.51 x 105 kg, to the nearest newton what is the magnitude of the retarding force?

Stopping Distance

A load of steel of mass 6000 kg rest on a flat bet truck. It is held in place by metal brackets which can exert a maximum horizontal force of 8000 N. When the truck is traveling 20 m/s, what is the minimum stopping distance if the load is not to slide forward into the cab?

Using Newton's Law

Question: A curve of radius 56 m is banked so that a car traveling with a uniform speed of 54 km/hr can round the curve without relying on friction to keep it from slipping to its left or right. What is theta?

Mass on a spring of structure-less body

Let m be the mass of a structureless body supported by a spring with a uniform force constant k . Set up the differential equation of motion that determines the displacement of the mass from its equilibrium position at time t when the intital conditions are x(0) = x0 and x'(0) = 0.

Linear Momentum and Collisions

A car with linear momentum 8.0 x 10^4 kg* m/s brakes to a stop in 5.0 seconds. What is the magnitude of the braking force?

Magnitude of the Gravitational Force

The mass of one small ball is 1.59 g, and the mass of another is 881 g. If the center to center distance between thse two balls is 13.5 cm, calculate the magnitude of the gravitational force that each exerts on the other. Please explain.

Newtons Laws and Friction with Pulleys

In the figure (see attachment) the coefficient of static friction between mass m1 and the table is 0.35, whereas the coefficient of kinetic friction is 0.25. a) What minimum value of m1 will keep the system from starting to move? m1 = ?kg b) What value of m1 will keep the system moving at constant speed? m1 = ?kg

Two Blocks and Two Pulleys System

A block of mass m_1 is attached to a massless, ideal string. This string wraps around a massless pulley and then wraps around a second pulley that is attached to a block of mass m_2 that is free to slide on a frictionless table. The string is firmly anchored to a wall and the whole system is frictionless. A) Given the magnit

Newtons Laws - centripetal force

The string of a conical pendulum is 50.0 cm long, and the mass of the bob is 0.250 kg. a) find the angle between the string and the horizontal when the tension is six times the weight of the bob. b) what is the radius of the circle in which the bob is moving? c) under those conditions what is the period of the pendulum?

Motion on an inclined plane

Determine the time time tB, tC, and tD needed for a block of mass m to slide from rest at A to points B, C, and D, respectively. Neglect effects of friction. See attachment for picture.

Coefficient of Friction for a Skier on a Hill

A skier is moving at 20.0 m/s down a 30 degree slope. He encounters wet snow and slides 145 meters before coming to a stop. What is the coefficient of friction between the skis and the snow?

Free Body Diagram

Please answer each question with step by step answers so I understand the solutions. Thanks! 1. The imperial units for mass is slugs, for length is feet and for time is seconds. The imperial units for force is a pound. What is a pound in terms of slugs, feet and seconds? 2. A box is on a sled. The sled is pulled up a hill

Application Of Newton's Second Law

A 400-kg ice boat moves on runners on essentially frictionless ice. A steady wind blows, applying a constant force to the sail. At the end of an 8.0s run, the acceleration is 0.50 m/s^2. a. What is the acceleration at the beginning of the run? b. What was the force due to the wind? c. What retarding force must be appl

How do you find the differential equation of motion?

A rope of mass M and length L lies on a frictionless table, with a short portion Lo hanging through a hole. Initially the rope is at rest. 1) Find a general equation for x(t), the length of rope through the hole. 2) Evaluate the constants A and B so that the initial conditions are satisfied

Momentum of Freight car containing a mass of sand

A freight car of mass M contains a mass of sand "m". At t=0 a constant horizontal force F is applied in the direction of rolling and at the same time a port in the bottom is opened to let the sand flow out at constant rate dm/dt. Find the speed of the freight car when all the sand is gone. Assume the freight car is at rest at

Find friction coefficient such that block m does not slip.

On a frictionless table a block of mass M=1.75 kg is attached to a spring of negligible mass whose force constant k= 60 nt/m. Riding on top of M but not attached to it, is a block m= .65 kg. The blocks execute SHM with amplitude Xm= .25 m. Find the minimum value of the coefficient of friction, u, between the two blocks, such t