Answer:
(a) The force between them quadruples
Explanation:
According to coulomb's law, initial force between the two charged objects is given as;

where;
k is coulomb's constant
q₁ is the charge on the first object
q₂ is the charge on the second object
r is the distance between the two objects
When the charges on both objects are doubled, then;
q₁ = 2q₁
q₂ = 2q₂
Force between the two charged objects will become

Therefore, the force between them quadruples
Answer: The first electromagnet has a more powerful current than
the second
Explanation:
Since the two electromagnets contain the same types of magnets and wires. If the magnet In the first moves much faster than the second. Therefore:
The first electromagnet has a more powerful current than the second
Because the induced EMF is proportional to the induced current.
Where the induced EMF depends on the speed of the magnet according to the formula below
EMF = BVL
So, increase in speed of the magnet will cause more powerful induced current and emf
If it produces 20J of light energy in a second, then that 20J is the 10% of the supply that becomes useful output.
20 J/s = 10% of Supply
20 J/s = (0.1) x (Supply)
Divide each side by 0.1:
Supply = (20 J/s) / (0.1)
<em>Supply = 200 J/s </em>(200 watts)
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Here's something to think about: What could you do to make the lamp more efficient ? Answer: Use it for a heater !
If you use it for a heater, then the HEAT is the 'useful' part, and the light is the part that you really don't care about. Suddenly ... bada-boom ... the lamp is 90% efficient !
Answer:
you were sopposed to divide
Explanation:
Precipitation is your answer. according to my science textbook, in a cold front, warm air and cold air interact and cause precipitation.