Answer:
B
Explanation:
nothing to do with black holes creating star or related
Answer:
The balloon would still move like a rocket
Explanation:
The principle of work of this system is the Newton's third law of motion, which states that:
"When an object A exerts a force on an object B (action), object B exerts an equal and opposite force (reaction) on object A"
In this problem, we can identify the balloon as object A and the air inside the balloon as object B. As the air goes out from the balloon, the balloon exerts a force (backward) on the air, and as a result of Newton's 3rd law, the air exerts an equal and opposite force (forward) on the balloon, making it moving forward.
This mechanism is not affected by the presence or absence of surrounding air: in fact, this mechanism also works in free space, where there is no air (and in fact, rockets also moves in space using this system, despite the absence of air).
Answer: The cylinder
Explanation:
Among all other solid shapes, the sphere has the smallest area for a given volume.
By experiment, the ratio of the radius of a sphere to a cylinder of equal volume is less than 1.
Recall;
That the Rate of transfer of convective heat (Q) = h × A ×change in temperature.
Where ,
h= the co efficient of convective heat transfer
A= the cross sectional area.
As such, since the sphere has a smaller surface area relative to the cylinder, the sphere transfers heat slower than the cylinder.
Therefore, if the sphere and cylinder are exposed to convection in the same environment, then, the cylinder cools faster.
PS; the more the Area, the higher the rate of heat transfer and vice versa.
Formula for kinetic energy is 1/2mv^2 so that answer should most probably be 94521.6J
Answer:
True
Explanation:
Driving safely at night requires seeing well not only under low light, but also requires drivers to see low-contrast objects.
