Answer:
11 m/s
Explanation:
Draw a free body diagram. There are two forces acting on the car:
Weigh force mg pulling down
Normal force N pushing perpendicular to the incline
Sum the forces in the +y direction:
∑F = ma
N cos θ − mg = 0
N = mg / cos θ
Sum the forces in the radial (+x) direction:
∑F = ma
N sin θ = m v² / r
Substitute and solve for v:
(mg / cos θ) sin θ = m v² / r
g tan θ = v² / r
v = √(gr tan θ)
Plug in values:
v = √(9.8 m/s² × 48 m × tan 15°)
v = 11.2 m/s
Rounded to 2 significant figures, the maximum speed is 11 m/s.
Answer:
As ice melts into water, kinetic energy is being added to the particles. This causes them to be 'excited' and they break the bonds that hold them together as a solid, resulting in a change of state: solid -> liquid.
Explanation:
As we may know, the change in state of an object is due to the change in the average kinetic energy of the particles.
This average kinetic energy is proportional to the temperature of the particles.
This is because heat is a form of energy; by adding energy to ice - heat, you "excite" the water molecules, breaking the interactions in the lattice structure and forming weaker, looser hydrogen-bonding interactions.
This causes the ice to melt. This is demonstrated in the image below.
More generally, when you remove energy - the object cools down, the particles move a lot slower. So slow, that they individually attract other molecules more than before, and this results in a physical change that also changes the state.
In thermodynamics, work of a system at constant pressure conditions is equal to the product of the pressure and the change in volume. It is expressed as follows:
W = P(V2 - V1)
W = 1.3x10^5 (2x6 - 6 )
<span>W = 780000 J
</span>
Hope this answers the question. Have a nice day.
Air pressure pushing in on the balloon decreases as the balloon rises.
