Sally, who has a mass of 55 kg, is sledding at the park. She places her 9-kg sled at the top of a hill and then runs with a velocity of 3 m/s and jumps on it. What is the combined velocity of Sally and the sled right after she jumps on, in m/s? (Round your answer to one decimal place if necessary.

Problem 3: A student of mass m = 51 kg runs at a velocity v; = 1.53 m/s before leaping on a skateboard. After leaping on the board the student has a velocity vf = 1.44 m/s. What is the mass of the skateboard, in kilograms? Numeric : Anumeric value is expected and not an expression. Mp =

A stationary soccer ball of mass m = 0.72 kg is kicked with a constant force of F = 29 N. The woman's foot is in contact with the ball for t = 0.24 s a) Write an expression for the speed of the ball, vi, as it leaves the woman's foot. (b) What is the velocity of the ball right after contact with the foot of the woman?

an iron ball with a mass of 67.5 kg is traveling with an initial velocity of 20.5 m/s. the ball is hit with a hammer, which remains in contact with the ball for 0.20 sec.  how much force must the hammer hit the ball with to cause it to change directions?

A ball struck by a bat experiences a change in momentum of 42 kg m/s . If the time of interaction is 0.29 s, what is the magnitude of the average force acting on the ball (in N) ?

A block of mass m1 = 14 kg slides along a horizontal surface (with friction, μk = 0.27) a distance d = 2.5 m before striking a second block of mass m2 = 8.25 kg. The first block has an initial velocity of v = 9.75 m/s. Assuming that block one stops after it collides with block two, what is block two's velocity after impact in m/s?  How far does block two travel, d2 in meters, before coming to rest after the collision?

During a car collision, the knee, thighbone, and hip can sustain a force no greater than 4000 NN. Forces that exceed this amount could cause dislocations or fractures. Assume that in a collision a knee stops when it hits the car's dashboard. Also assume that the mass of the body parts stopped by the knee is about 20% of the total body mass. The person with a mass of 90 kgkg is initially traveling at 18 m/sm/s (40 mi/hmi/h).  What minimum stopping time interval in needed to avoid injury to the knee?  What is the minimum stopping distance?

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During a collision with a wall, the velocity of a 0.200-kg ball changes from25.0 m/stowardthe wall to 20.0m/s away from the wall. If the time the ball was in contact with the wall was 0.03s, what was the magnitude of the average force the wall applied on the ball?

An exploding coconut with a total mass of M breaks into three pieces.  Piece C has a mass of 0.3M and piece B has a mass of 0.2M.  If piece C has a velocity vfC= 7.9 m/s, determine the velocity of piece A, vfA