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Newton's Second Law

Determining magnitude and direction of net force

A 1380 kg car is moving due east with an initial speed of 27.0 m/s. After 8.00 s the car has slowed down to 17.0 m/s. What is the magnitude and direction of the net force that produces the deceleration.

kinetic energy and potential energy

(See attached file for full problem description) 26. A block of mass m is initially moving to the right on a horizontal frictionless surface at a speed v. It then compresses a spring of spring constant k. At the instant when the kinetic energy of the block is equal to the potential energy of the spring, the spring is compress

Average force between ball and bat

A 0.14-kg baseball with an initial speed of 28 m/s rebounds with a speed of 34 m/s after being struck with a bat. If the duration of contact between ball and bat was 2.1 ms, what was the average force between ball and bat? I need to see each step and formula to solve this question.

Impulse momentum theorem

A croquet mallet delivers an impulse of 8.83 N seconds to a 0.44-kg croquet ball initially at rest. What is the speed of the ball immediately after being struck? I need to see each step and formula to solve this question.

Force with Coefficient of Friction

Find the force P necessary to push a 50.6 kg block down an incline of 32.4 degrees with an acceleration of 1.78 m/s^2. P is parallel to the incline and the coefficient of friction between the block and the incline surface is 0.805. Picture is attached.

Banked Curves and Newton's Laws

Banked Curve I. A curve with a 120-m radius on a level road is banked at the correct angle for a speed of 20 m/s. If an automobile rounds this curve at 30 m/s, what is the minimum coefficient of static friction between tires and road needed to prevent skidding?

Finding the Magnitude of Horizontal Forces

(See attached file for full problem description with diagram) --- Block A in the figure weighs w1 and block B weighs w1. The coefficient of kinetic friction between all surfaces is uk. 1. Find the magnitude of the horizontal force necessary to drag block B to the left at constant speed if A rests on B and moves with it (f

Newton's law - mechanics problem involving a frictionless pulley

(See attached file for full problem description with diagram) --- A block with mass is placed on an inclined plane with slope angle and is connected to a second hanging block that has mass by a cord passing over a small, frictionless pulley. The coefficient of static friction is and the coefficient of kinetic friction is

Netwon's Law of Motion and Force

I need help how to show the expression / equation for this problem: A dockworker applies a constant horizontal force of (F) to a block of ice on a smooth horizontal floor. The frictional force is negligible. The block starts from rest and moves a distance (x) in a time (t1). If the worker stops pushing at the end of (t1),

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