A few Physics questions....?

Question

1- What is the equation for Kinetic Energy and Momentum?

2- What is the difference between an inelastic and elastic collision?

3- What does conservation of momentum mean?

4- A mosquito splats against the windsheild of a car travelling down the interstate at some large but legal velocity. Which has the largest change of momentum from the collision?

- the car
- the mosquito
- the road
- none of the above


Thanks for your help.

Thanks gebobs!

Okay I'm confused..


Is it mosquito or none of the above??

or the car..


I'm really confused now...

Answer 1

1- Kinetic Energy= 0.5*m*v^2
Momentum=v*m

where m is the mass, and v is the velocity

2- Slight idea, but I do not want to confuse you with my ideas.Hence, I will not answer this question.

3-For a collision occurring between object 1 and object 2 in an isolated system, the total momentum of the two objects before the collision is equal to the total momentum of the two objects after the collision. That is, the momentum lost by object 1 is equal to the momentum gained by object 2.

4-Since the car's momentum is not going to really change (it will change negligibly) because it has a much higher momentum than the mosquito. While the mosquito's momentum is overpowered by the car's, it is flinged the opposite direction. Since, momentum is a vector quantity, the mosquito's momentum is reversed, changing dramatically.
And therefore 'mosquito' is the answer.

Answer 2

kinetic energy=(mass x v^2)/2
elastic collision results in a backwards acceleration....in this case the kinetic energy has nowhere to go, so an object moves backwards if colliding
inelastic collision...in this case kinetic energy is released on both objects collided resulting in a roadkill!
poor mosquito......well the car has a higher speed i can bet so we use the equation above and i really believe the car is quite heavier than the mosquito so the car has the largest momentum

Answer 3

1. KE = ½mv²
...p = mv

2. With elastic collision, no energy is lost in the collision.

3. It means that the sum of the momenta of all bodies in a system always stays the same, neglecting energy dissipation. of course.

4. None of the above. The road doesn't experience a change. By the above law, the changes in momenta for the car and the mosquito must cancel out i.e. they are equal.

Answer 4

the answers are all same to the first answers, except the last one....the mosquito will have the largest change in momentum, because it has a very low weight and ofcourse it wouldnt make the car go back,instead the car pushes it backwards..