The diagram shows a collision between a 4.0 kg toy car and a stationary 8.0 kg toy truck. After the collision, the car bounces back at 1.0 m/s while the truck goes forward at 2.0 m/s. Based on these values, are momentum and kinetic energy conserved?
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I think that both are conserved but that is not the correct answer.
I cannot paste the link to the image.
To determine whether momentum and kinetic energy are conserved in a collision, you need to consider the before and after values of these quantities.
Momentum is defined as the product of an object's mass and velocity. In this case, the momentum before the collision can be calculated by multiplying the mass of the car and the velocity at which it is approaching the truck. Similarly, the momentum of the truck before the collision can be calculated by multiplying the mass of the truck (which is stationary) by its velocity before the collision (which is zero).
After the collision, the car is bouncing back at 1.0 m/s, while the truck is moving forward at 2.0 m/s. To calculate the momentum after the collision, you can use the same equation as before, considering the masses and velocities of the car and truck after the collision.
To assess whether momentum is conserved, you need to compare the total momentum before the collision to the total momentum after the collision. If they are equal, then momentum is conserved.
Now, kinetic energy is given by the equation KE = 0.5 * mass * velocity^2. Similarly to momentum, you can calculate the kinetic energy before and after the collision for both the car and the truck. To assess whether kinetic energy is conserved, you need to compare the total kinetic energy before the collision to the total kinetic energy after the collision. If they are equal, then kinetic energy is conserved.
By performing these calculations, you can determine whether momentum and kinetic energy are conserved in this specific collision scenario.