At a busy intersection, a 1320-kg car traveling west with a speed of 12 m/s collides head-on with a minivan traveling east with a speed of 9.4 m/s. the cars stick together and move with a velocity of 1.5 m/s to the east after the collision. what is the mass of the minivan

p = mv so this question pertains to conservation of momentum.

The momentum of the car is 1320*12 = 15840kgms^-1
For the sake of easiness and the fact negatives are annoying, I will assume east to be positive.

So we know 9.4m - 15840 = (1320+m)*1.5
9.4m - 15840 = 1980+1.5m

Rearranging to solve for m
7.9m = 17820
m = 2255.70 = 2300kg to 2sf

From negative to negative

Answerthe energy required is 1.60 × 10⁻¹⁸ j, to three significant figures.explanationwe define electric potential as the ratio electric potential energy to the charge,    then the following gives us the potential difference,      the formula  may be on your formula sheet.the change in electric potential energy would be the energy that would needed to move it from point a to point b. solving for that, we get    using q = 8.00  × 10⁻¹⁹ c and  δv = 2.00 v, we get    the energy required is 1.60 × 10⁻¹⁸ j, to three significant figures.