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Calculating Recoil Velocity

Starting from rest, two skaters "push off" against each other on smooth level ice, where friction is negligible. The little one has a mass of 54-kg and the bigger one has a mass of 88-kg. Assuming the little one coasts away with a velocity of 2.5 m/s due north, determine the recoil velocity of the bigger skater.

Average Force Exerted

A 140 gram baseball has a velocity of 38 m/s as it approaches a bat. The bat applies a force and the ball departs in the opposite direction at 58 m/s. The contact time between the bat and the ball is 4.0 ms. Determine the average force exerted on the ball by the bat.

"Ball Kick"

A man kicks a 200g ball such that it leaves the ground at an angle of 30 degrees with the horizontal and strikes the ground at the same elevation a distance of 15m away. Determine the impulse of his foot on the ball. Neglect the impulse caused by the ball's weight while its being kicked.

Block Up Ramp

A 5-lb block is given an initial velocity of 10 ft/s up a 45 degree smooth slope. Determine the time it will take to travel up the slope before it stops.

Force, Velocity, Potential Energy (Energy Law)

A girl has a mass of 40kg and center of mass at G. If she is swinging to a maximum height defined by theta = 60 deg, determine the force developed along each of the four supporting posts such as AB at the instant theta = 0 deg. The swing is centrally located between the posts. *See attachment for diagram

Conservation of momentum

Jonathan and Jane are sitting in a sleigh that is at rest on frictionless ice. Jonathan's weight is 800 N, Jane's weight is 600 N, and that of the sleigh is 1000 N. They see a poisonous spider on the floor of the sleigh and immediately jump off. Jonathan jumps to the left with a velocity (relative to the ice) of 5.00 m/s at 30 d

Analyzing Elastic Collision in One Dimension

Blocks of mass m and 2m are positioned on a semicircular frictionless track at a height of R/4 above the lowest point. The blocks are released simultaneously and collide elastically. How high does each block rise after the collision?

Rocket Ejection and Linear Momentum

A rocket with initial mass of 8.0 x 10^3 kg is fired vertically. Its exhaust gases have a relative velocity of 2.5 x 10^3 m/s and are ejected at a rate of 40 kg/s. a) What is the initial accerleration of the rocket? b) What is the acceleration after 20s have elapsed?

Angular momentum

A hockey stick of mass m_s and length L is at rest on the ice (which is assumed to be frictionless). A puck with mass m_p hits the stick a distance D from the middle of the stick. Before the collision, the puck was moving with speed v° in a direction perpendicular to the stick. The collision is completely inelastic, and the pu

Deer Hunting Kinematics

A man is deer hunting by a cliff that is 1000.0 m tall. He fell asleep while hunting and woke up at night. He decided to shoot off a few rounds to try and get the attention of someone. If he aims 65 degrees above the horizontal and fires a bullet that leaves his gun at 410.00 m/s over the cliff how long will the bullet rise?

Two problems in basic Physics: Force and Direction

Problem 1: A box of mass M is held against the ceiling by a force P acting at an angle (SYMBOL1) as shown. The block slides along the ceiling to the right at a constant speed. The coefficient of kinetic friction between the box and the ceiling is (SYMBOL2). (a) Draw a labled free body diagram for the box (b) Determine the f

Toy Car: Actual translational speed of the car; angular velocity of the flywheel

When a toy car is rapidly scooted across the floor, it stores energy in a flywheel. The car has mass 0.180g, and its flywheel has a moment of inertia of 4.00*10^(-5)kg.m^2. The car is 15.0cm long. An advertissement claims that the car can travel at a scale speed of up to 700km/h (440mi/h). The scale speed is the speed of the toy

Mechanics: velocity and kinetic energy

A Steel pile is driven a distance (d) into the ground by a hammer of mass (M) 450kg, dropped from a height (h) of 3.25m above the top of the pile. The mass of the pile (m) is 40kg and the average resistance of the ground to penetration (Fr) is 45kN. Calculate: a. The velocity and the kinetic energy of the hammer immediatel

Momentum of a Broken Spaceship Piece After Explosion

A spaceship of mass 2.3*10^6 kg is cruising at a speed of 4.4*10^6 m/s when the antimatter reactor fails, blowing the ship into three pieces. One section, having a mass of 5.1*10^5 kg, is blown straight backward with a speed of 2.1*10^6 m/s. A second piece, with mass 7.6*10^5 kg, continues forward at 1.1*10^6 m/s. What is the sp


A 160 kg hockey puck is moving on a icy, frictionless, horizontal surface. at t=0 the puck is moving to the right at 3m/s 1) Calculate the velocity of the puck(magnitude and direction) after a force of 25N directed to the right has been applied for 0.050s 2)If instead, a force of 12N directed to the left is applied from t=0 t

Momentum, Velocity and Force

A baseball has mass 1) if the velocity of a pitched ball has magnitude 45m/s and the batted ball's velocity is 55m/s in the opposite direction, find the magnitude of the change in momentum of the ball and the impulse applied to it by the bat. b) If the ball remains in contact with the bat for 2.00ms, find the magnitu

Three-Block Inelastic Collision

A block of mass m1 moving with speed v1 undergoes a completely inelastic collision with a stationary block of mass m2. The blocks then move, stuck together, at speed v2. After a short time, the two-block system collides inelastically with a third block, of mass m3, which is initially stationary. The three blocks then move, stu

Question about Shooting over a Hill

See attached A. Find the highest point in the trajectory, . Express the highest point in terms of the magnitude of the acceleration due to gravity , the initial velocity , and the angle . B. What is the range of the projectile, ? Express the range in terms of , , and . Consider your advice to an artiller

Circualr Motion

The period of a stone swung in a horizontal circle on a 2.00-m radius is 1.00 s. a. What is its angular velocity in rad/s? b. What is its linear speed in m/s? c. What is its radial acceleration in m/s^2.

Velocity - Addition Formula

As seen from earth (rest frame S) two rockets A and B are approaching in opposite directions...See Attachment

Ballistic Pendulum measures projectile speeds

A ballistic pendulum is a great device for measuring projectile speeds that are relatively large. You launch a small mass m into a large mass M, and it swings up a height h where the two masses stick together. Show that the velocity of the projectile (mass m) is given by v= (m+M)/m) times the square root of 2gh

A block of mass m slides on a frictionless table. It is constrained to move inside a ring of radius l which is fixed to the table. at t=0, the block is moving along the inside of the table (i.e., in the tangential direction) with velocity (v)O (v initial) , the coefficient of friction between the block and the ring is "u" 1) find the velocity of the block at later times 2)find the position of the block at later times

A block of mass m slides on a frictionless table. It is constrained to move inside a ring of radius l which is fixed to the table. at t=0, the block is moving along the inside of the table (i.e., in the tangential direction) with velocity (v)O (v initial) , the coefficient of friction between the block and the ring is "u" 1)