answer is :D it would be a great answer
Answer:
<em>a. True</em>
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Explanation:
I'll assume the question is about magnetic latches and locks.
Magnetic door locks use an electromagnetic force to stop doors from opening, so they are ideal for security. There are two main types of electric locking devices. Locking devices can either be a fail-secure locking device that remains locked when power is lost, or a fail-safe locking device that is unlocked when de-energized. An electromagnetic lock creates a magnetic field when energized or powered up, this causes an electromagnet and armature plate to become attracted to each other strongly enough to keep a door from opening.
Answer;
D. ocean currents might change course.
Explanation;
Ocean currents are the directed movements of water in the ocean and can be caused by wind (for currents closer to the surface) and temperature, salinity, or density differences (currents deeper in the ocean). Ocean currents help to warm or cool certain parts of the earth by carrying warmer water northward or cooler water toward the equator.
Climate change can have a vast effect on ocean currents because of the change in temperature it causes, which results in change in ocean water temperatures and a subsequent distortion in current flow.
Answer:
a
The speed of wave is 
b
The new speed of the two waves is 
Explanation:
From the question we are told that
The mass of the string is 
The length is 
The tension is 
Now the velocity of the first wave is mathematically represented as
Where 
is the linear density which is mathematically represented as
substituting values
So
Now given that the Tension, mass and length are constant the velocity of the second wave will same as that of first wave (reference PHYS 1100 )
