(adsbygoogle = window.adsbygoogle || []).push({}); [SOLVED] Momentum problem (Car and object)

1. A crash test car with mass 1,000 kg moving at a constant speed of 12 m/sec collides completely inelastically with an object of mass M at time t=0. The object was initially at rest. The speed V in m/sec of the car-object system after the collision is given as a function of time t in seconds by the expression V= 8 / (1+5t).

a) Find the mass M of the object.

b)Assuming an initial position of x=0, determine an expression for the position of the car-object system after the collision as a function of time t.

c)Determine an expression for the resisting force on the car-object system after the collision as a function of time t.

d)Determine the impulse delivered to the car-object system from t=0 to t=2 sec.

2. Equations for the conservation of momentum.

m1*v1 + m2*v2 = (m1 +m2)*v'

3. a)I found the mass M to be 500 kg because at time=0 (time of collision), V= 8 m/sec. I used the equation for perfectly inelastic collisions.

b)The derivative of position function is equal to the velocity function, so I need to integrate. When I did that, there was a zero in the bottom of the fraction. Can't divide by zero.

c) ?

d) impluse = force*time. I assume that I need to know the equation in part c to find d. Once I know the function in part c, d is found by the area under the graph.

Thanks in advance!! :)

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Momentum problem (Car and object)

**Physics Forums | Science Articles, Homework Help, Discussion**