Answer:
As the car travels up the coaster it is gaining potential energy.
Explanation:
Because It has the greatest in amount of potential energy at the top of the coaster. when the car travels down the roller coaster it obtains speed and kinetic energy.
Given that,
Initial velocity , Vi = 0
Final velocity , Vf = 40 m/s
Acceleration due to gravity , a = 9.81 m/s²
Distance can be calculated as,
2as = Vf² - Vi²
2 * 9.81 *s = 40² - 0²
s = 81.55 m
For half height, that is, s = 40.77m
Vf= ??
2as = Vf² - Vi²
2 * 9.81 * 40.77 = Vf² - 0²
Vf² = 800
Vf = 28.28 m/s
Therefore, speed of roller coaster when height is half of its starting point will be 28 m/s.
Answer:
The option is B is not true for Hubble telescope.
Answer:
(A)The water will freeze.
Explanation:
Heat is the energy that when transferred causes change in temperature. If heat is added to a body by some process the bodies temperature increases and if heat is removed from a body by some process the temperature reduces.
In this case if enough heat is removed from the room the internal movement of the water particles will slow down causing the water to form crystal lattice thus forming ice. So, the water will freeze.
