Exam 8: Systems of Particles and Conservation of Linear Momentum

Glider A,traveling at 10 m/s on an air track,collides elastically with glider B traveling at 8.0 m/s in the same direction.The gliders are of equal mass.The final speed of glider B is

An automobile of mass 1300 kg has an initial velocity of 7.20 m/s toward the north and a final velocity of 6.50 m/s toward the west.The magnitude and direction of the change in momentum of the car are

In riot control,the riot squad uses a water hose that shoots water at a rate of 5 m/s and volume of 40 L/s.What is the average force exerted on a person assuming that the water splashes sideways in all directions? The density of water is 1000 kg/m³.

Two equal masses travel in opposite directions with equal speeds.They collide in a collision that is between elastic and inelastic.Just after the collision,their velocities are

The condition necessary for the Conservation of Linear Momentum in a given system is that

A Saturn V rocket with an initial mass m₀ of 3 $\times$ 10⁶ kg has a payload that accounts for 27% of this mass,a burn rate of 15 $\times$ 10³ kg/s,and a thrust F_th of 35 $\times$ 10⁶ N.The acceleration at lift-off is

A 7000-kg coal car of a train coasts at 7.0 m/s on a frictionless track when a 3000-kg load of coal is dropped vertically onto the car.The coal car's speed after the coal is added is

Two identical cars approach an intersection.One is traveling east at 18 m/s.The second is traveling north at 24 m/s.They collide violently,sticking together.Immediately after the crash they are moving

A 20-g bullet is fired into a 2.0-kg block of wood placed on a horizontal surface.The bullet stops in the block.The impact moves the block (+ bullet)a distance of 5 m before it comes to rest.If the coefficient of kinetic friction between the block and surface is 0.25,calculate the speed of the block (+ bullet)system immediately after impact.

A car having a total mass of 2250 kg and traveling at 72.0 km/h smashes into a tree.The car is stopped in 0.250 s.The average force acting on the car during the collision is

A 200-g ball dropped from a height of 50 cm rebounds to a height of 35 cm after impact.The change in momentum of the ball is

A Saturn V rocket with an initial mass m₀ of 3 $\times$ 10⁶ kg has a payload that accounts for 27% of this mass,a burn rate of 15 $\times$ 10³ kg/s,and a thrust F_th of 35 $\times$ 10⁶ N.The burn time t_b is

Water is fired horizontally out of a 7-cm diameter hose directly onto a wall at a speed of 7m/s.Assuming that the water after impact falls straight down the wall,the average force on the wall is (density of water = 1000 kg/m³ )

A ball of mass m strikes a wall that is perpendicular to its path at speed +v and rebounds in the opposite direction with a speed -v.The impulse imparted to the ball by the wall is

A particle of mass 2m is moving to the right in projectile motion.At the top of its trajectory,an explosion breaks the particle into two equal parts.After the explosion,one part falls straight down with no horizontal motion.What is the direction of the motion of the other part just after the explosion?

A bullet (mass = m)is fired at speed V into a block of mass M (with M>m)which is hanging vertically from a light string of length L.The bullet stops in the block.If the recoiling block + bullet system reaches a height of 2/3L,then the initial speed of the bullet is given by

A car of mass 1850 kg is traveling at 22.5 m/s in a straight line.A truck of mass 3170 kg has the same momentum as the car.The speed of the truck is

In any and all collisions of short duration and for which it is true that no external forces act on the collision participants,

In a coordinate system whose center of mass moves with a velocity _c,the total momentum in the center-of-mass coordinate system after collision of the two masses m₁ and m₂ is

If the momentum of a mass M is doubled,its kinetic energy will be multiplied by a factor of