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Conservation of Momentum

Conservation of Angular Momentum of a Large Turntable

A large turntable rotates about a fixed vertical axis, making one revolution in a time of T. The moment of inertia of the turntable about this axis is I. A child with a mass of m, initially standing at the center of the turntable, runs out along a radius. What is the angular speed of the turntable when the child is a distance

Linear Momentum and Collision: Maximum Spring Compression

Two particles with masses m1=2.0kg and m2=5.0kg are free to slide on a straight horizontal frictionless guide wire. The particle with the smaller mass is moving with speed of 17.0m/s and overtakes the larger particle, which is moving in the same direction with a speed of 3.0m/s. The larger particle has an ideal inertia-less spri

Newton's 3rd Law.

Newton's 3rd Law 1) The two forces in each pair may have different physical origins (for instance, one of the forces could be due to gravity, and its pair force could be a normal contact force). True / False? 2) The two forces of a 3rd law pair always act on different bodies. True / False? 3) Given that two bodies in

Motion In A Plane:Projectile with explosion at the top

A projectile that is fired from a gun has a initial velocity of 90.0 km/h at an angle of 60d above the horizontal. When the projectile is at the top of its trajectory, an internal explosion causes it to separate into two fragments of equal mass. One of the fragments falls straight downward as though it had been released from res

Rotational Forces - Spaceship

A space station shaped like a giant wheel has a radius of 105 m and a moment of inertia of 5.03 108 kgm2. A crew of 150 are living on the rim, and the station's rotation causes the crew to experience an apparent free-fall acceleration of g (Fig. P10.44). When 100 people move to the center of the station for a union meeting, the


Most of us know intuitively that in a head-on collision between a large dump truck and a subcompact car, you are better off being in the truck than in the car. Why? Many people imagine that the collision force exerted on the car is much greater than that experienced by the truck. To substantiate this view, they point out that th

Force, Collision and Conservation of Linear Momentum

A car (m1) is traveling at a velocity (v1) and it smashes into a wall. In situation 1: the car bounces off in a completely elastic collision with no change in speed. In situation 2: the car stops by inelastic collision. Which situation would be the most dangerous. Why? ----------------------------------------------------------


A 45.5 kg girl is standing on a plank that has a mass of 143 kg. The plank, originally at rest, is free to slide on a frozen lake, which is a flat, frictionless supporting surface. The girl begins to walk along the plank at a constant speed of 1.41 m/s relative to the plank. (a) What is her speed relative to the ice surface?

Skeet shooting maximum height

A 0.250 kg skeet (clay target) is fired at an angle of alpha = 32.6o to the horizon with a speed of v0 = 29.3 m/s, as seen in figure below. When it reaches the maximum height, it is hit from below by a 15 g pellet traveling vertically upward at a speed of v = 186 m/s. The pellet is embedded in the skeet. How much higher did t

Mechanics: Perfectly Inelastic Collision

A) One lump of clay traveling at 27 m/s overtakes a second lump traveling at 5.6 m/s. After collision they are stuck together. To the nearest tenth of a m/s what is their common velocity? B) If the second lump in the above problem was moving in the opposite direction before the collision what would be the answer?

Inelastic Collision: Conservation of Momentum

Question: On a very muddy football field, a 110-kg linebacker tackles an 85-kg halfback. Immediately before the collision, the linebacker is slipping with a velocity of 8.8 m/s north and the halfback is sliding with a velocity of 7.2 m/s east. What is the velocity (magnitude and direction) at which the two players move together


Block 1, of mass = 3.30, moves along a frictionless air track with speed = 31.0. It collides with block 2, of mass = 15.0 , which was initially at rest. The blocks stick together after the collision A.) Find the magnitude of the total initial momentum of the two-block system. Express your answer numerically. B.) Fi

Mass of Puck in a Situation with Another Puck

Puck 1 of mass m1=.20kg is sent sliding across a frictionless lab bench, to undergo a one-dimensional elastic collision with the stationary puck 2. Puck 2 then slides off the bench and lands a distance d from the base of the bench. Puck 1 rebounds from the collision and slides off the opposite edge of the bench, landing a distan

Moment of inertia

Moment of inertia of a circular ring of mass M and radius a about a line through its centre perpendicular to its plane

Ignoring and Including Special Relativity

A satellite is at rest in space when destroyed by a hostile alien space ship. One piece that is 100 kg floats away at a speed of 0.80C. Another piece floats away with a speed of 0.90C away from the explosion in the opposite direction. What is the mass of the piece that flew away in traveling at 0.90C. Determine this two ways

Rate of rotation

A diver can change her rate of rotation in the aair by "tucking" her head in and bending her knees. Let's assume that when she is stretched out straight she is rotating at 1 revolution per second. Now she goes into the "tuck and bend", effectively shortening the length of her body by half. What will her rate of rotation be now?

Inertia Ratio between Solid Spheres of Different Mass

Consider two uniform solid spheres where both have the same diameter, but one has twice the mass of the other. The ratio of the larger moment of inertia to that of the smaller moment of inertia is a. 10 b. 4 c. 6 d. 2 e. 8

Momentum of a Ball of Putty

A 3kg ball of putty moving at 1 m/s collides and sticks to a 2kg ball initially at rest. The putty and ball then move with a momentum of:

Solving a conservation of momentum problem

How fast must a 10.5g bullet be traveling when it strikes a ballistic pendulum that consist of a block of wood of mass 3.0kg that is suspended by a cord? The bullet gets embedded in the block. The block rises by .22m after the impact. a. 143 m/s b. 595 m/s/s c. 595 m/s d. 2.67 m/s

Conservation of Momentum and Collision Review

1. A car crashes into a wall at 25 m/s and is brought to the rest in 0.1 s. Calculate the average force exerted on a 75-kg test dummy by the seat belt. 2. A railroad diesel engine weighs four times as much as a freight-car. If the diesel engine coasts at 5 km/h into a freight-car that is initially at rest, how fast do the

Solving: Linear Momentum and Collisions

Problem: Two billiard balls of equal mass move at right angles and meet at the origin of an xy coordinate system. One is moving upward along the y axis at 2.0 m/s, and the other is moving to the right along the x axis with speed 3.8 m/s. After the collision (assumed elastic), the second ball is moving along the positive y axis.

Linear Momentum: Child in a Boat

A child in a boat throws a 6.00 kg package out horizontally with a speed of 10 m/s. Calculate the velocity of the boat immediately after, assuming it was initially at rest. The mass of the child is 24.0 kg and that of the boat is 50.0 kg.

More simple physics

A 0.025kg bullet traveling at 305m/s strikes a 1.500 kg ballistics pendulum hanging from a 2.00 m long string and buries itself in the block. How many degrees backward will the block swing? Do not use the law of conservation of momentum.

Variable Mass and Conservation of Linear Momentum

The problem is related to variable mass systems. A cylinder is moving through dust particles and the particles are sticking to it. A mass in the form of a solid cylinder, of radius c acted upon by no forces, moves parallel to its axis through a uniform cloud of fine dust, of volume density , which is at rest. If the partic

Classical mechanis, conservation of total momentum

Two cars, both of mass m, collide and stick together. Prior to the collision, one car had been traveling north at speed 2v, while the second was traveling at speed v at an angle omega south of east. After the collision, the two-car system travels at speed v_final at an angle theta east of north. What is the angle theta with resp

Propeller Flow - Momentum Equation

Consider a ducted propeller system, which is moving forward at a velocity V1. Analyse the system by assuming the duct remains stationary, as shown in the above diagram. If, for a specific design and point of operation, V2/V1=9/4 and V1/V2=5/4, then what is the thrust produced by the propeller in terms of the pressures at 2 and 3

Conservation of Angular Momentum: Suspended Rod

The 6lb slender rod AB is originally shown at rest, suspended in the vertical position. A 1lb ball is thrown at the rod with the velocity v= 50ft/s and strikes the rod at C. Determine the angular velocity of the rod just after the impact. Take e = 0.7 and d= 2ft. (See attachment for diagram)

Angular Momentum and Conservation of Angular Momentum

A uniform 2.45kg spinning disk with a radius of 0.243m is brought to rest by a brake pad pressed against the side 0.183m from the rotation axis. The wheels is brought to rest from an angular velocity of 15.4rad/s in a time of 24.3s. What frictional force was applied by the brake pad.