Power is the RATE at which energy changes or flows.
The unit of energy is the Joule, so a unit of power is the Joule/second.
That unit has the special name "<em>Watt</em>".
Your question is not necessarily a question. It's also a statement, You could write
"<em>Watt's the basic unit of the measurement of power</em>".
Answer: sound waves or cosmic rays
Explanation:
Cosmic radiation consist of high energy particles,x-rays and gamma rays produce in space
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




You should disconnect all wires from the circuit or make sure the switch is off or batteries are out