A, Mechanical and A, Chemical.
Answer:
The magnetic flux through the desk surface is 
.
Explanation:
Given that,
Magnetic field B = 0.42 T
Angle =68°
We need to calculate the magnetic flux
Where, B = magnetic field
A = area
Put the value into the formula
Hence, The magnetic flux through the desk surface is .
Answer:
The acceleration of the mass is 2 meters per square second.
Explanation:
By Newton's second law, we know that force (
), measured in newtons, is the product of mass (
), measured in kilograms, and net acceleration (
), measured in meters per square second. That is:
(1)
The initial force applied in the mass is:
In addition, we know that force is directly proportional to acceleration. If the smaller force is removed, then the initial force is reduced to 
of the initial force. The acceleration of the mass is:
The acceleration of the mass is 2 meters per square second.
Answer:
High speed optical communication technology
To be able to communicate from the space to the earth and from earth to space is one of the most essential features required during space exploration.
Explanation:
Space exploration involves going into the space, beyond the earth's atmosphere. Landing on other planets and studying their details, going into deeper space beyond the planets to discover new cosmic events or structures is all a part of space exploration.
The key to analyse the studies and observations is being able to communicate the data collected, photos taken etc to the launch centers or space centers on earth. The space centers on earth should also be able to communicate with the persons or the satellites in space.
This is made possible using the optical communication technology which involves the use of optical fibers, lasers etc, since high speeds are more efficient during communication
Neutron is commonly used to initiate a fission chain reaction.
