Two 110 kg bumper cars are moving toward each other in opposite directions. car a is moving at 8 m/s and car z at –10 m/s when they collide head–on. if the resulting velocity of car a after the collision is –10 m/s, what is the velocity of car z after the collision?

Explanation:

Mass of bumper cars,

Initial speed of car A,

Initial speed of car Z,

Final speed of car A after the collision,

We need to find the velocity of car Z after the collision. Let it is equal to . Using the conservation of momentum as :

So, the velocity of car Z after the collision is (-12 m/s). Hence, this is the required solution.

answer: 802.3 kilo joules of energy represents 191.75 kilo calorie of energy.

explanation:

energy released during combustion of one mole methane = 802.3 kilo joules

if 1 kilo joule = 0.239006   kilo calorie

then ,802.3 kilo joule will be = 802.30.239006 kilo calorie

802.3 kilo joule = 191.75 kilo calorie

hence, the energy in kilo calorie is 191.75 kilo calorie.

air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.