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cedgraham
Jan 27, 2010, 03:17 PM
If a Mack truck and a motorcycle have a head-on collision, upon which vehicle is the impact force greater? Which vehicle undergoes the greater change in its motion?

KUXJ
Jan 27, 2010, 03:27 PM
Hi! cedgraham, welcome to AMHD :)

I would say the answer to both questions would be the motorcycle, because it has less mass than the Mack truck. :eek:

ebaines
Jan 29, 2010, 08:50 AM
Actually, forces are equal and opposite, so both vehicles feel the same force. However, the resulting change in velocity of the motocycle is much greater (due to its lighter mass). Just as when a golfer hits the ball with his driver- the force of collision is the same on the ball and the club face, but because the ball weighs a lot less the velocity of the ball changes a lot more (from rest to perhaps 100 MPH) than does the club face (which hardly slows down in its swing at all).

KUXJ
Jan 29, 2010, 09:31 PM
Actually, forces are equal and opposite, so both vehicles feel the same force. However, the resulting change in velocity of the motocycle is much greater (due to its lighter mass). Just as when a golfer hits the ball with his driver- the force of collision is the same on the ball and the club face, but because the ball weighs a lot less the velocity of the ball changes a lot more (from rest to perhaps 100 MPH) than does the club face (which hardly slows down in its swing at all).Would it be true to say...
Impact forces develop which are unique to each individual situation.

It is the transference at the point of application of the larger mass's potential energy to the smaller that creates the magnitude, direction, and line of action.

Thanks, ebaines, I defiantly need to visit Sir Isaac this week...
K

ebaines
Jan 30, 2010, 07:59 AM
Almost right - it's not the transfer of potential energy, but rather kinetic energy. In an elastic collision two conditions must be satisfied:

1. Conservation of energy: the sum of the two object's masses times its velocity squared must remain constant before and after the collision

2. Conservation of momentum: the vector sum of the system's momentum must remain constant.

KUXJ
Jan 30, 2010, 09:25 AM
If cedgraham doesn't return soon we are going to have to start our own thread.

I don't have time now to pursue, but would like to discuss
the potential energy, but rather kinetic energy angle.

Is there a dedicated thread to discuss Newton's laws?
I won't be able to get back until 10pm or so my time (est).

K

FlyYakker
Jan 31, 2010, 03:37 PM
Forces are equal and opposite. Reaction of the two bdies are unequal due to the difference in mass.