Explanation:
Given that,
Mass of a freight car, 
Speed of a freight car, 
Mass of a scrap metal, 
(a) Let us assume that the final velocity of the loaded freight car is V. The momentum of the system will remain conserved as follows :

So, the final velocity of the loaded freight car is 0.182 m/s.
(b) Lost on kinetic energy = final kinetic energy - initial kinetic energy
![\Delta K=\dfrac{1}{2}[(m_1+m_2)V^2-m_1u_1^2)]\\\\=\dfrac{1}{2}\times [(30,000+110,000 )0.182^2-30000(0.85)^2]\\\\=-8518.82\ J](https://tex.z-dn.net/?f=%5CDelta%20K%3D%5Cdfrac%7B1%7D%7B2%7D%5B%28m_1%2Bm_2%29V%5E2-m_1u_1%5E2%29%5D%5C%5C%5C%5C%3D%5Cdfrac%7B1%7D%7B2%7D%5Ctimes%20%5B%2830%2C000%2B110%2C000%20%290.182%5E2-30000%280.85%29%5E2%5D%5C%5C%5C%5C%3D-8518.82%5C%20J)
Lost in kinetic energy is 8518.82. Negative sign shows loss.
( 3 yr) · (186,282.397 mile/s) · (86,400 s/day) · (365 day/yr)
= (3 · 186,282.397 · 86,400 · 365) mile
= 1.762380502 x 10¹³ miles
= 1.8 x 10¹³ miles (rounded to the nearest trillion miles)
The 'strength' of the electric field is the force on 1C of charge at that point.
At this 'certain location', the field is 40/5 = 8 newtons per coulomb = <u>8 volts</u>
When you add more water to the balloon, it makes it heavier. Therefore it would weigh the balloon down ( increasing mass) and increasing the energy to plummet down. So the answer is B.
Wave speed = frequency * wavelength
Wave speed = 4 * 25
Wave speed = 100 m/s