Your answer would be
B. 7.3 KG
At A, coaster is only associated with potential energy.
At B, coaster is associated with kinetic as well as potential energy.
Since the track is frictionless, no energy will be lost when coaster reaches from point A to point B. Therefore, according to conservation of energy, total energy at A should be equal to total energy at B.
Total energy at A = mgh = mg(12)
Total energy at B = mgh+ mv²/2 = mg(2) + mv²/2
∴12mg = 2mg + mv²/2
∴(12g-2g)×2 = v²
∴v² = 20g
∴v = 14m/s.
Again conserving energy at points B and C.
Total energy at B = 2mg + m(14)²/2
Total energy at C = 4mg + mv²/2
∴2mg + m(14²)/2 = 4mg + mv²/2
Solving this you get,
v = 12.52 m/s.
Therefore, speed of roller coaster at point C is 12.52 m/s.
Answer:
Gravitational attraction of the sun.
Explanation:
Gravity is an attractive force. Any two masses will exert an attractive force on the other according to Newton's law of universal gravitation. The more massive the objects, the stronger the force. The sun, as you can probably guess, is pretty massive - 330,000 times more than Earth, and 1,048 time more than Jupiter, our solar system's largest planet. Just like man-made satellites around Earth, the planets in our solar system are constant process of "falling" around the sun, locked in their orbits by its mass, but slowing dramatically in their orbital velocity the further away they are.
C. Hypothesis
The hypothesis is presented as an explanation of the observed results.