If you're referring to the different colors that usually occur at the tip of missles, rockets and some other aircraft, it either a) signifies the end of a particular plate of metal, fabricated specifically to be for the nose. Sometimes these can even be a different alloy or metal all together. or b) this shows where the curved surface begins, so in the case of damage or imperfections due to wear, they can be repaired and measured more easily. The shape of the nose is extremely important for smooth flight, and a dent or bump formed on it can make the aircraft unstable. If you can measure from where the curve starts by the difference in color, it makes repairing or re-fabricating the part much easier. Many of these curves aren't as simple as they appear.
Answer:
a. 
b.
must be the minimum magnitude of deceleration to avoid hitting the leading car before stopping
c.
is the time taken to stop after braking
Explanation:
Given:
- speed of leading car,

- speed of lagging car,

- distance between the cars,

- deceleration of the leading car after braking,

a.
Time taken by the car to stop:

where:
, final velocity after braking
time taken


b.
using the eq. of motion for the given condition:

where:
final velocity of the chasing car after braking = 0
acceleration of the chasing car after braking

must be the minimum magnitude of deceleration to avoid hitting the leading car before stopping
c.
time taken by the chasing car to stop:


is the time taken to stop after braking
<h2>Answer:</h2><h2>The depth of barge float=
3 cm</h2><h2>
Explanation:</h2>
Length of rectangular barge=5.2 m
Width of rectangular barge=2.4m
Mass of crate=410 kg
Let h be the height of barge float
Volume of barge float=
Density of water=
Weight of water displaced by barge=Buoyant force=-Weight of horse



1 m=100 cm
cm
Hence, the depth of barge float=3 cm
<h2 />
The material that the cylinder is made from is Butyl Rubber.
<h3>What is Young's modulus?</h3>
Young's modulus, or the modulus of elasticity in tension or compression, is a mechanical property that measures the tensile or compressive strength of a solid material when a force is applied to it.
<h3>Area of the cylinder</h3>
A = πr²

<h3>Young's modulus of the cylinder</h3>

Where;
When 5 kg mass is applied, the extension = 10 cm - 9.61 cm = 0.39 cm = 0.0039 m.

When the mass is 50 kg,
extension = 10 cm - 7.73 cm = 2.27 cm = 0.0227 m

The Young's modulus is between 0.001 GPa to 0.002 GPa
Thus, the material that the cylinder is made from is Butyl Rubber.
Learn more about Young's modulus here: brainly.com/question/6864866