Answer:
<u>Electromagnetic introduction</u> is the production of an electromotive force (voltage) across an electrical conductor in a changing magnetic field.
- <em><u>Step up transformers</u></em><u> is</u> a transformer in which the output (secondary) voltage is greater than its input (primary) voltage is called a step-up transformer. The step-up transformer decreases the output current for keeping the input and output power of the system equal.
- <u><em>Step down transformer is </em></u><em>a transformer in which the output (secondary) voltage is less than its input (primary) voltage is called a step-down transformer. The number of turns on the primary of the transformer is greater than the turn on the secondary of the transformer.</em>
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<u>The difference between them:</u>
A transformer is a static device which transfers a.c electrical power from one circuit to the other at the same frequency, but the voltage level is usually changed. For economical reasons, electric power is required to be transmitted at high voltage whereas it has to be utilized at low voltage from a safety point of view. This increase in voltage for transmission and decrease in voltage for utilization can only be achieved by using a step-up and step-down transformer.
Hopefully this helped.
Answer: The softer barrier is the better option
Explanation:
1) When is a car is moving at a certain speed, it has a certain amount of momentum (p=mv). A collision against a barrier would cause its momentum to decrease to 0. A change in momentum is Impulse
2) The formula for Impulse: J = f * Δt
J is Impulse
f is the force applied during the time Δt
A tough barrier would produce a smaller Δt, which means more force is applied on the car. (J is always constant)
A softer barrier would apply less force on the car, which means Δt is large.
Answer: The softer barrier is the better option
Melting, of course. Just as how an ice cube melts to water.
Answer: 0.2m
Explanation: Firstly only the Rocket's Weight Compress the spring which can be found by

According to Hooks Law

The part b and c of this question is done in the attachment
The red, yellow, and green wavelengths of sunlight are absorbed by water molecules in the ocean. ... In coastal areas, runoff from rivers, resuspension of sand and silt from the bottom by tides, waves and storms and a number of other substances can change the color of the near-shore waters.