Physics
posted by Bobby .
A 45 kg cart is moving across a frictionless floor at 1.7 m/s. A 60 kg boy, riding in the cart, jumps off the cart so that he hits the floor moving forwards in the initial direction of the cart's motion with a velocity of 2.8 m/s. What is the velocity of the cart after the boy jumped?

Physics 
Damon
initial mass = 45 + 60 = 105 kg
initial momentum = 105 * 1.7 = final momentum
so
105*1.7 = 2.8*60 + 45 v 
Physics 
Bobby
but how do you go from 105*1.7 = 2.8*60 + 45 v to the answer?? i'm so confused!

Physics 
bobpursley
This is pretty basic algebra.
subtract 2.8*60 from each side. Then divide both sides by 45.
Respond to this Question
Similar Questions

physics
A 50. kg cart is moving across a frictionless floor at 2.0 m/s. A 70. kg child, riding in the cart, jumps off so that the child hits the floor with zero velocity. What was the velocity of the cart after the boy jumped? 
physics
A 50. kg cart is moving across a frictionless floor at 2.0 m/s. A 70. kg child, riding in the cart, jumps off so that the child hits the floor with zero velocity. What was the velocity of the cart after the boy jumped? 
physics
A 48 kg cart is moving across a frictionless floor at 3.3 m/s. A 50 kg boy, riding in the cart, jumps off the cart so that he hits the floor with zero velocity. a.What is the velocity of the cart after the boy jumped? 
PHYSICS
A Few questions please help!!! also show steps! What magnitude of force, acting for 0.025 s, will change the velocity of a 100 g ball from 30 m/s eastward to 40 m/s westward? 
Physics
A cart on an airtrack is moving at 0.5m/s.when the air is suddenly turned off the cart comes to rest after traveling 1m the experiment repeated but now the cart is moving at 1m/s when turned off .how far does the cart travel the cart … 
Physics
Two boys standing on carts that move along a horizontal frictionless surface. The mass of each boycart combination is 100 kg, and each moves initially with the velocities of: Boy A 7cm/sec and Boy B: 10cm/sec. The boy on cart A throws … 
physics
A 10.0 kg cart and a 15 kg cart are locked together with a compressed spring between them. They are then released so that the spring pushes the two carts apart. The 10.0 kg cart is moving at 3.0 m/s afterward. How fast is the 15 kg … 
Physics 1
A cart with mass 340 g moving on a frictionless linear air track at an initial speed of 1.5 m/s undergoes an elastic collision with an initially stationary cart of unknown mass. After the collision, the first cart continues in its … 
physics
A full shopping cart requires a force of 88.0 Newtons to move across a horizontal floor at a constant velocity. If the cart has a mass of 32.1 kg, what is the coefficient of kinetic friction between the cart and the floor? 
Physics
A 50 kg boy runs at a speed of 10 m/s and jumps onto a cart. The cart is initially at rest. The speed of the cart with the boy on it is 2.50 m/s. a)What is the initial momentum of the boy?