5. Two students are sitting next to each other on chairs with wheels. The boy has a mass 75 kg, and the girl has a mass of 50 kg. They push each other and separate in opposite
directions. This causes the boy to move at 2 m/s. How fast and in what direction is the girl
moving? Is this an elastic or inelastic collision?

In which situation is the acceleration of a car negative? question 5 options: a)the velocity of a car was 75 km/hr over 4 hours. b)the velocity of a car reduced from 50 km/hr over one minute. c)the velocity of a car increased from 40 km.h to 75 km/h over 15 minutes. d)the velocity of a car was 45 km/hr at 2: 00pm and at 4: 00pm its velocity was 85 km/ht.

The first law of thermodynamics states that heat added to a system is neither created nor destroyed but is as it changes into other forms of energy.

What explosion in the upper solar atmosphere releases about as much energy as millions of 100-megaton hydrogen bombs exploding simultaneously?