Answer:
(a) 89 m/s
(b) 11000 N
Explanation:
Note that answers are given to 2 significant figures which is what we have in the values in the question.
(a) Speed is given by the ratio of distance to time. In the question, the time given was the time it took the pulse to travel the length of the cable twice. Thus, the distance travelled is twice the length of the cable.

(b) The tension,
, is given by

where
is the speed,
is the tension and
is the mass per unit length.
Hence,

To determine
, we need to know the mass of the cable. We use the density formula:

where
is the mass and
is the volume.

If the length is denoted by
, then


The density of steel = 8050 kg/m3
The cable is approximately a cylinder with diameter 1.5 cm and length or height of 620 m. Its volume is




Answer:
a planet
Explanation:
If planetesimals, objects that combined to form protoplanets, were to collide head on in the early solar nebula, they would shatter to the point where they would be unable to grow into a larger size, a protoplanet. A protoplanet is a massive object that will eventually become a planet.
It’s important for a scientist to be open-minded because they need to be able to understand or creative anything that was never thought about. It’s also important for a scientist to be skeptical because some ideas or products that they hear about can have false factors. I hope this helped!
Answer:
Both AC and DC describe types of current flow in a circuit. In direct current (DC), the electric charge (current) only flows in one direction. Electric charge in alternating current (AC), on the other hand, changes direction periodically.
The kinetic molecular theory of matter offers a description of the microscopic properties of atoms (or molecules) and their interactions, leading to observable macroscopic properties (such as pressure, volume, temperature). An application of the theory is that it helps to explain why matter exists in different phases (solid, liquid, and gas) and how matter can change from one phase to the next.