Answer:
4 seconds
Explanation:
There are links between cars, they are in between
1-2, 2-3, 3-4, 4-5, 5-6, 6-7, 7-8, 8-9, 9-10, 10-11, 11-12, 12-13, 13-14, 14-15, 15-16, 16-17.
Here 1 represents the first car which is firmly attached to the engine. So, there are 16 links and each link has a slack of 9 m.
So, total slack
9×16 = 144 cm
Speed of train = 36 cm/s

Time taken by the pulse to travel the length of train is 4 seconds.
Answer:
1) a radio are uses by astronomy
2) 6 bilion waves
3) expert vertified
Explanation:
1) in contrast to an "ordinary" telescope, which receives visible light, a radio telescope "sees" radio waves emitted by radio sources, typically by means of a large parabolic ("dish") antenna, or arrays of them.and Radio telescopes are also the primary means to track space probes, and are used in the SETI project. so must been
radio are almostly
ceiver by astronomy
2) Radio waves have the longest wavelengths in the electromagnetic spectrum.
3)Expert Verified
Radio telescopes are telescopes that are specially designed for observation of long light wavelengths
CARRY ON ✨
Answer:
<h2>30 N</h2>
Explanation:
The force acting on an object given it's mass and acceleration can be found by using the formula
force = mass × acceleration
From the question we have
force = 15 × 2
We have the final answer as
<h3>30 N</h3>
Hope this helps you
All the boats operating at night requires Navigation light.
Navigation light helps prevent collisions between boats and see if visibility is poor. The types of boat are : Rowboats, Tug boats, Vessels, Sailboat etc.
Various boats have different lightning color to show its use and side of the boat.
It is a wedge because of the ramp thingy